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Hey guys,

First off, I apologize for the length here. I like to be thorough and my hope is for this to be THE resource for a noob (like myself) to be able to swap in a ZF 5 transmission from start to finish for a 1980-1986 Bronco, a year-set I have not seen covered yet. Please feel free to ask any questions or suggest better ways to do things. Before I get into it my personal suggestion on how to go about the swap is to purchase a parts truck for the transmission and pull some of the manual components from a JY truck.

FULL DISCLOSURE: I HAVE FINISHED THE ZF 5 SWAP BUT AM PUTTING THE FINISHING TOUCHES ON MY ENGINE SO I HAVE NOT DRIVEN WITH THE ZF 5 YET. WILL UPDATE THIS POST WITH ANYTHING I LEARN AT THAT POINT.

A. FINDING A PARTS TRUCK
B. PARTS LIST
C. ZF 5 REMOVAL
D. JUNKYARD PARTS TRUCK
E. C6 REMOVAL
F. ZF 5 INSTALLATION
G. CLOSING THOUGHTS

A. Finding a Parts Truck

So the first thing you want to do on this project IMO is to find a late 1987-1997 4x4 F250+ with a small block engine (300, 302, 351W) and the transmission (duh). A couple points. Firstly, it is entirely possible to do this swap by purchasing the transmission and the rest of the needed parts as you go, but IMO it's a lot easier to have everything from one spot and to be able to see how it came off in order to swap it over. Secondly, there are actually 2 sub models of the ZF 5, the S542 which was used from late '87-'94 and the S547 on '94-'97s. I won't go too in depth here, but from what I understand there were some small improvements to the construction of the transmission that lead to the S547. At the end of the day both will work, but for more specifics I suggest your own research. So a quick intro on Ford's Door Panel Stickers. They are located on the inside of the driver’s side door panel and look like this:


So what we are looking for here is under TRANS (lower right) we want to see a "W". I've also heard of a "Z" or a "2" being there but have never ran across one myself. Be careful to confirm it’s not an "M" which is the M5OD tranny. The ZF 5 also has a very particular cross-pattern design.

I suggest searching images of the M5OD so you can tell the difference. Also, yes, you could theoretically get 4x2 model tranny and switch it over but it's really not worth the hassle.
Once you’ve found one make sure to shift through all the gears and make sure it’s still shifting smoothly. I’d also suggest to examine the exterior of the tranny for any cracks, specifically around the bellhousing area. Ask me how I know.

B. Parts List

So I'll prime this by saying you'll need quite a bit of specific things from specific places (you'll see what I mean). Included is my suggestion of where to acquire each part. If you’re not sure what something is read through the installation section where I tried to have pictures of everything. I sourced my new parts from @RockAuto so I’ll include part numbers of what I used where applicable.

Parts Truck= 1988-1997 F250+ Truck
JY Truck= Late 1983-1986 F150+
New= source these parts for usage in 1988-1999 F250+ trucks
*note* some parts from the JY truck can be acquired from an '80-'86 F150+ while others need to be from late '83-'86 when Ford converted to the hydraulic clutch. I'm going on the assumption you are pulling them at the same time so I'd suggest to limit your search to an '83-'86*

-ZF 5 Transmission (Parts Truck)
-Shifter/Boot/Bezel (Parts Truck)
-Shifter Plate (Parts Truck)
-Crossmember (Parts truck or any M5OD equipped F150+)
-Manual Engine Dust Cover (Parts Truck)
-Manual Starter (Parts Truck)
*note* Manual and automatic transmissions use different starters*
-Clutch Pedal Assembly (JY Truck)
-Steering Column (JY Truck)
*note* steering column isn't necessary if you don't mind having a non-operational gear selector on the column
-Backup Light Indicator Wire (JY Truck)
-Flywheel (164 tooth) (New or Parts Truck) Brute Power 50735
-11” Clutch Kit (10” is okay too but not as heavy duty) (New or Parts Truck) Brute Power 90284
-Internal Slave Cylinder (New) Brute Power 37897
*note* Although not a requirement you’ll be kicking yourself if you have to take this whole thing apart to replace the cylinder*
-Hydraulic Hose (New) Brute Power 85203
-Transmission Mount (New) Westar EM2557
-Driveshafts (see note)
*note* If stock you should be able to use the front driveshaft from your parts truck, rear will require a custom built driveshaft or a M5OD driveshaft from a Bronco*
-Master Cylinder (New or parts truck) AMS M0706
I’d suggest to by the pre-bled master/slave cylinder if you can find one. These things aren’t too fun to bleed yourself. I used these parts for my S5-42 transmission so make sure to double check all parts before buying!

Note: Regarding the transfer case, you have 3 different options. The simplest option first, you can use your existing NP208 case, but you’ll need to source both the correct shift linkage and shifter plate from the JY Truck. These years utilized the shifter plate for both shifters so you wouldn’t be required to cut the hole for your transfer case shifter. Next you could buy a BW1356 from a post 1988(I believe) Bronco. And lastly the option I went with: use the BW1356 from the parts truck with some modification. The reason for the modification is that the rear shafts were different on the F-Series trucks and BKOs transfer cases. It’s not a terribly difficult swap, but if I had to do it over I’d probably just go with option 2. You will require the driveshaft from the post 1988 era if you go with option 2 or 3. The differences are highlighted in this.

http://www.fullsizebronco.com/forum/21-noobie-bronco-tech-questions-flame-free-zone/38886-b-w-1356-manual-transfer-case-rebuild.html

C. ZF 5 Removal

Alright now for some nitty gritty. Let’s get that ZF off the parts truck!
Start by placing the truck into neutral. Then begin removing the 4 screws on the shifter bezel.

Remove the 4 5mm Allenhead screws from the shift tower cover and remove entire shifter assembly.

Remove the 4 screws from transfer case shifter bezel.

Remove the 2 8mm bolts securing the transfer case shifter.

Pull back the carpet to reveal what I’ll refer to as the transmission shifter plate.

Remove the 9 8mm bolts and remove plate. This will give you a lot better access to the top bolts on the transmission.
There are 6 bolts in all that actually secure the tranny to the engine. Red are the bolts, blue are the 2 alignment dowels.

I’ll take a quick tangent to suggest you pick up one of my favorite tools. It’s the Bostich rotating handle ratchet from Wal-Mart ($20) and it made this whole job easier. Instead of working with the limited space to try and turn your ratchet, you just crack the bolt and twist the handle. Personally I can’t recommend this thing higher. I have zero affiliation with Bostich just love this ratchet.
For those interested: https://www.walmart.com/ip/Bostitch-Rotator-Ratchet/49021388
So from up top remove the 2 5/8” bolts. You’ll need an extension or 2.
Now head underneath the truck! Remove the remaining 4 5/8” bolts on each side of the tranny. Keep these bolts for reference as I suggest you get new ones.
Next disconnect your relay to starter wire from your starter. Then remove the 2 ½” starter bolts and remove the starter.

Disconnect the backup light indicator wire (blue circle), speedometer cable from the transfer case and any other misc. wires.

Now mark (so they’ll stay balanced) and remove both driveshafts. You’ll need to put a screwdriver between to keep it from spinning. Each U-joint has 4 nuts. Nuts are ½”

While not necessary, I suggest draining the ZF 5 and your transfer case to make removal a little easier.


Remove the 2 ¾” tranny mount bolts.

Next you’ll want to start removing your crossmember. It actually consists of 3 separate parts, the actual crossmember and two gussets. Pictured below are the C6 components but you get the idea.

You’ll want to remove the bolts from the gussets first. Because we are switching the whole thing over, they need to be completely removed. Position a tranny jack or whatever you’re using to get this thing out. I’ve seen some people use an engine hoist positioned in the door with some heavy-duty straps around the tranny. Others make a custom wood-made tranny jack, or you can use an actual transmission jack. Whatever you’re using position it so you can raise the tranny up.
After you do, remove the bolts on the crossmember.

Slide it back, pull the driver’s side back and rotate the crossmember until you can clear the frame and remove.
Make sure to disconnect the hydraulic line since you have access now. Now you know why the suggestion is to swap out the slave cylinder while you have it out! You should have tool with your new hydraulic line and/or slave cylinder that lets you detach the connection. Looks like this.

Now you should be able to claim your tranny! I jacked the truck up to be able to clear the frame.
But you’re not quite done yet. Remove the 6 bolts on the clutch pressure plate and remove. Careful, it’s heavy!

Now remove the 6 bolts on the flywheel. An impact wrench makes this job infinitely easier. Make sure you’re holding on to the flywheel as you do this as it can easily fall.

Now you should have access to the dust plate. I didn’t take a picture but it’s basically a bellhousing shaped metal plate with a hole for the starter.
Next dump the truck into a fiery abyss cause you’re all done with it!
 

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Discussion Starter #2
D. Junkyard Parts Truck
So you've got the tranny and the rest of your parts from your parts truck but you'll still need a couple things. As previously stated, these parts can be sourced at the Junkyard. We're looking for an '83-'86 manual transmission Bronco or more likely F-150+. I suggest using an app like Row52.com or your local JYs website to set an alert for whenever one comes in. They aren't impossible to find, just set up an alert asap and one should pop up. For those not trying to go the JY route I have seen most of these parts pop up on eBay. Some of the magazines offer them too (LMC, etc.) but you're definitely paying for it.

So as a quick recap we'll need the following from our JY truck:

Clutch Pedal Assembly


Steering Column (JY one will not have gear selector obviously)


Backup Indicator Light Wire



Circled below is where this will plug in to give you a better idea of what you’re looking for.



Getting any of these parts isn't entirely difficult, but I will give a quick walk through of the process.

You’ll have to take the steering column out to access the clutch pedal assembly anyway so let's start there. Start by removing the steering column plastic cover. There are two knobs on the left most side of the dash panel.


Using a pair of pliers, push in the tabs behind the knobs and pull them off. Then remove the dash panel by unscrewing all attaching screws, I believe there’s about 4-6, and pulling the panel off. Be careful to maneuver it around the column so you don’t snap a piece off.


Next follow the steering column to the firewall and remove the 5 3/8” bolts from the plate. The ratcheting wrench I referenced above was a big help in the tight quarters.


Then head under the hood and remove the 5/8” bolt that connects the column to the shaft. Remove the bolt and the securing clip.



Head back in the cab and remove the 6 9/16” bolts that clamp the column to the pedal assembly. This will cause the column to drop since nothing is supporting it.

Undo all connections, I believe there are about 3, taking note of where you’ll be attaching them in your BKO. My finger is pointing at one and then there are 2 that look like the one sitting on the ground. There’s also vacuum line to disconnect.


You should be able to wriggle the column out at this point. It may take some back and forth between the hood and cab as you pull it and it gets caught along the way.
Now you’ll have much clearer access to the pedal assembly. Begin here by using pliers to pull the pin from brake pedal that secures the booster rod. Slide everything attached off.


Do the same on the other side on the clutch pedal. DO NOT REMOVE THE NUT ON TOP. Simply remove the pin on this side and slide the clutch master cylinder rod off. Thanks again to @AbandonedBronco for this tidbit. Apparently the nut is a splined press fit and can only be installed once. You take it off and you need a new one. Only problem is nobody makes them anymore so you’ll need a whole new clutch assembly. So let’s just avoid that whole endeavor entirely shall we?

Disconnect the wires on the right and left side of this picture.


Next peek your head directly underneath the pedal assembly and you’ll see the 2 hidden bolts that secure it to the dash as well as a third directly in front of those.


Remove the 4 9/16” bolts that secure the assembly to the firewall. They are actually attached to the brake booster.


Now you’ll need to head back under the hood and pull the brake booster out so we’ll have enough room to remove the assembly.
At this point you can head back into the cab and recover your prize! I found it easiest to basically grip the bottom of the assembly and maneuver it out, being careful of the clutch pedal attachments on the left.
Also while we’re here, since our master cylinder doesn’t come with the nuts to tighten it to the firewall let’s grab them here. They are located inside the cab just to the right of the brake pedal.
You’re almost done! Head underneath the truck and on the driver’s side frame you should see a wire attachment that looks like this.

Disconnect it and its end and you have everything you need!

E. C6 Removal

So, I’m gonna save myself the writing and you the reading by making this simple. This process is more or less the same as the ZF 5 removal with a few variations that I will highlight below. We’ll also go over the difference in removing your column as well.
We’ll start with the column. Looking on the left side of the column, just behind the steering wheel you’ll see a looped wire around a stud. This is your gear selector wire.


Using pliers remove it from the loop and either cut the wire off at the top or position it to the side. I kept mine on but there’s not a great reason to.

Before you go to pull the column head under the hood and you’ll see the shift linkage. As you can see I wriggled it loose up top and removed the nut from below. Not sure if it’s the best way but it worked for me.


There’s not a real lot different from there other than since the C6 is an automatic you’ve got a torque converter and flexplate. The torque converter is heavier than you think and full of fluid so be careful there.
You will want to remove the tranny cooler lines. Trace them up to the front and remove completely.
Also, take note of the electrical connection you disconnect from the tranny that sits on the frame. You’ll be using it later for your backup light indicator.

F. ZF 5 Installation

Alright my friends we’ve finally arrived. Let’s get that ZF 5 where it’s always belonged, in your BKO! I definitely took quite a bit less pictures as I just wanted to get this in so I’ll do my best to explain. It really is the reverse of the of the removal process. This is a great time to switch out your motor mounts and rear main seal. My engine was already out from a rebuild so I’ll leave it to you to get those done if you so choose. I’ll be reusing some pictures from above for clarity purposes.

First things first, let’s replace the clave cylinder. Remove the 2 bolts and slide it off. Also if yours looks anything like this as you go to install you’re doing it wrong.

Simply slide your new one on and tighten it back down. Then attach your hydraulic line. The trick is to have it fully inserted until you can slide the clip in. Once you have it attached be careful not to kink or otherwise break it.
Next is the pedal assembly. Maneuver it in until you can line it up with the brake booster stud holes. Once you do go ahead and throw your brake booster back in.

Before tightening the studs down, insert and tighten the 3 bolts that secure the assembly to the dash. I prefer to do this first for alignment purposes.

Now go ahead and tighten the 4 9/16” nuts to the brake booster studs.
So with everything else out this is a good time to cut some holes for the new stuff you need. We’ll need to cut holes for the clutch master cylinder and the transfer case shifter. Let’s hit the master cylinder location first. If you’re lucky like I was you’ll have some indentations to the left of your brake booster. Turns out Ford did us the favor of having all frames, whether auto or manual, stamped with these starter indentations. I am not quite certain when this began or ended but on my ’86 they were there. Look carefully, they’re quite easy to miss, but they should look like this.

The three vertical indents above the stud hole in the bottom left.
If you do your job here is pretty simple. Grab your gasket from your master cylinder set and line it up to give yourself an idea of what you’re trying to accomplish. I don’t remember the exact size bits I used but just compare the studs from the master cylinder and you’ll need a little bigger than that for the top and bottom holes. Make sure you drill straight! Alignment with the pedals here is crucial and you only get one shot! The middle hole requires a hole saw bit. I unscrewed the cylinder rod and experimented until I found the right size. I believe it was 1” but you should double check.
If you aren’t lucky enough to have those indentations my best suggestion is to take measuring tape to the JY when you’re pulling off the rest of your parts and get the info there.
Either way when all is said and done it should look something like this, but with the stud holes drilled as well obviously.

Insert the master cylinder studs into the freshly drilled holes and attach the rod to the pedal assembly. Insert the securing pin. Using the nuts we grabbed from the junkyard secure the master cylinder in its new home. While we’re here we’ll reattach out brake booster rod and brake light connection. Don’t forget to secure with the pin.
Next we’ll want to cut the hole for our transfer case shifter. I went up to the auto store and purchased some gasket material. Make sure it’s at least 7” tall. Back on my parts truck I cut a template of the hole.

Take some measurements of how far off the shifter plate it is. Once again double check everything as we’ve only got one shot at this. Using your template and measurements trace an outline for us to drill out. I, or my dad I should say, used a sawzall to cut this portion. Before doing so double check below the truck that you won’t be sawing off anything. Try to leave as much metal as possible between the tranny shifter plate hole and your new hole. In the end it should look something like this, sans tranny obviously.

Now grab your new steering column for install. I was in an odd situation where the PO had already done a steering column swap so my tumbler key already didn’t work for my outside locks. So I skipped this step but most of you will want to keep your current key so make sure you switch the tumbler from your old column over. Since I didn’t do this step I can’t help you out much here other than to point you to the Chilton or Haynes manual.
This is a bit of a 2 person job getting everything lined up. Insert your new column through the firewall as a buddy lines it up to the shaft under hood. Go ahead and throw your clip and bolt back on.

Tighten down the 5 3/8” bolts that hold the plate to the firewall. This is a good opportunity to reattach our electrical connections. There are 2 of these connections so refer to your notes to make sure youre attaching everything correctly.

On the bottom right is a new connection for us. I believe it’s the equivalent of a NSS in later model trucks. You’ll have to pull the looped plug pictured below that’s in your truck currently and plug it in. It connects to the blue circled connection in the second picture.


The orange circle connection I am still uncertain about. Once I track down a wiring diagram I’ll update this thread. Any ideas please reply here.
Tighten the 6 9/16” bolts that secure the column to the pedal assembly.

Head under the truck with your dust plate, new flywheel and new clutch kit! Dust plate goes on first. Then our flywheel. The flywheel only lines up one way so if your holes aren’t lining up keep turning it until it does. Once again a buddy is useful here to hold the flywheel as you thread in the bolts. Don’t forget threadlock!

I’m stealing @Dan90FSB idea of lying on your back under the engine and using your knees to stop a breaker bar on the balancer. This will stop the engine from rotating as you torque the 6 bolts to 80 ft-lbs.
Then using a similarly sized socket, evenly knock your pilot bearing in.
Next, using your alignment tool, line the clutch pressure plate and clutch up on the pilot bearing. Follow the instructions with your clutch to tighten in sequence.


Alright so now we’re really ready to put this thing in! Begin by jacking your truck up and sliding the tranny under the frame. Oh and for the record I ended up using the transfer case from the parts truck. Either one should work as Ford stuck with the 10 spline design for quite some time. I am still shoring up how the connections work out and will update when I know more.
I like @Dan90FSB idea of making your own alignment dowels out of grade 3 or 5 7/16-4” bolts with a slight variation. He suggested to cut off the tops and make a spot for a flathead screwdriver to remove. When I cut off the ends and had it at about 3.5” it would get caught at a weird angle and not let me push the tranny closer to the engine. It worked best for me at about 2”. I also suggest only barely threading them in as removal gets pretty tough with the full weight of the tranny on it. DON’T FORGET THE SCREWDRIVER HOLES! Also, take it from me 2 is the magic number here for how many bolts to use. Put them in the second pink holes from the bottom (ummmmmm…..yeah can’t phrase that differently).


Now once again it’s up to you whether you want to connect it with or without the transfer case. Personally I did it unattached since I was having a hell of a time getting this thing aligned. After several attempts with an engine hoist I ended up using a couple of jacks strategically positioned so I could angle the tranny as I needed. Once again, I do not suggest this way as it’s not the safest but with a couple people it can be done.



So the key here is to line the tranny spline up with the pilot bearing at the correct angle. Use the alignment dowels to help guide you as well. Once you have it up on the dowels it’ll take some jiggling around to get it as tight as possible. However because the pressure plate is doing its job and pushing away its necessary to strategically tighten the tranny bolts. I started left top, hit right bottom, left bottom and right top slowly tightening them as I went.


Once you have those pretty tight you should be able to remove your dowels using the slit you cut for a flathead. Insert the real bolts and tighten those as well. Torque all to 50 ft-lbs
Now grab your crossmember from your parts truck and angle it in until it’s straight across.

Due to the design differences in the crossmembers we’ll actually be lining the bolt up on the hole towards the rear on the frame. Its about an inch away from the one the C6 crossmember used. Torque 45-55 ft-lbs.


While we have the tranny jacked up still slide the tranny mount into position on the crossmember. It’s important to put it on the right way or it will not line up correctly. Luckily most manufacturers stamp “REAR” on the, get this, rear. Lower the tranny and once you have it lined up correctly torque the mount to tranny bolts 45-60 ft-lbs. Then the mount to crossmember nuts and washers 60-80 ft-lbs.


Now torque the gussets, first the frame to gusset, then the gusset to crossmember bolts 45-55 ft-lbs. Its now safe to completely remove your jack or engine hoist.
Connect your transfer case and tighten bolts. Couldn’t find any torque specs but they don’t need much.
Replace your speedometer cable and clip.
Grab your backup light indicator cable and attach the frame connection first. I had to loop the cable around the crossmember gussets a few times and then connected to the backup indicator light plug.




Throw your MANUAL starter on and torque 15-20 ft-lbs.


Throw your front driveshaft from your parts truck and torque to spec.


Now just a few things in the cab. Line the shifter plate up with appropriate holes and tighten the 9 8mm bolts.


Reattach the shifter, bezel and boot for both the transmission and transfer case shifters.



Then we get to one of the worst parts of the whole swap. Bleeding the clutch. Follow the procedures below. Its more of a PITA than anything. Credit to @Steve83


Concentric Slave Cylinder Bleeding
1. Disconnect the coupling at the transmission with Coupling Disconnect Tool T88T-70522-A or equivalent by sliding the white plastic sleeve toward the slave cylinder while applying a slight tug on the clutch tube.
2. Clean dirt and grease from around the reservoir cap.
3. Remove cap and diaphragm and fill reservoir to the step with Heavy Duty Brake Fluid C6AZ-19542-AA or -BA (ESA-M6C25-A) or equivalent. Brake fluid must be certified to DOT 3 specification. By hand, apply 10-15 pounds to clutch pedal; if pedal is hard (.25-.50 inch) movement, skip to Step 9. If pedal is spongy, proceed to next step.
4. Using a small screwdriver, depress the internal mechanism of the male coupling to open the valve. While continuing to hold the valve open, slowly depress the clutch pedal to the floor and hold.
5. Remove the screwdriver from the coupling, closing the valve.
6. Release the clutch pedal.
NOTE:
The reservoir must be kept full at all times to ensure there will be no additional introduction of air into the system.
7. Refill reservoir to level at step.
8. Repeat steps 4 through 7 one time.
9. Close reservoir. Reconnect the coupling to the slave cylinder. Check that the connection is secure by applying a slight tug to the clutch tube.
10. Stroke the clutch pedal as rapidly as possible for five to ten strokes.
11. Wait one to three minutes.
12. Repeat Steps 10 and 11 three more times.
13. Loosen bleed screw (located in the slave cylinder body next to the inlet connection).
14. Depress and hold clutch pedal while tightening bleed screw 3-5 N-m (2.2-3.7 ft-lb).
15. Refill the reservoir to level at step.
16. The hydraulic system should now be fully bled and should properly release the clutch.

Don’t forget to refill your tranny and transfer case! Use a GL-4 based oil such as Red Line MT-90 for best results.

G. Closing Thoughts

As stated above I will update this after I actually run this thing. Overall as a process though I will say although this was challenging it’s far from impossible. If you have any sort of tranny experience this should be a bit of a breeze. Some of the cutting can be a little intimidating for some but I will tell you I had zero experience as long as you take your time and double measure you’ll be fine. Congrats on your new tranny! Also I’m sure I’m forgetting something so if you notice something missing please let me know!
 

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First off, great write up. Thanks for going into so much detail.

Next, my impression is that 97 was the last year for the f250+ with a small block. In 98, the f250 was a "light duty" basically just a 98 f150 with 7 lug axles. As far as I know these had the modular engines. There was no f350 that year. Not sure if there was an f450+ that year and if there was, not sure what engines they had. Also, the 99 f250 and f350 were the super duties which had the modular engines or powerstroke or maybe a v10. They did have the option for a zf transmission, not sure if it was a 5 speed or the zf6, a 6 speed version. At any rate, the modular engines have a different bolt pattern so their trans won't work. Again, not sure about the f450+ in 99.

Next, if you don't want a custom rear driveshaft you can use the driveshaft from a bronco with the m5od. The m5od is the same overall length as a zf5 so both the front and rear driveshafts are the same length on both trans.

Now, about the t-cases. I didn't notice whether you used the bronco or f250 case. The case in the pictures looks like a bw-1356, which was probably the case in both the bronco and the f250 so I guess it really wouldn't matter. Most people use the case originally mated to the zf5 if the bronco and the donor truck had 2 different cases. Not sure why, maybe the crossmember mounts different or it's because the driveshafts would be different. At any rate, the earlier broncos had a different case such as the np208f or a bw-1345. Something for others reading this to keep in mind.

As a note, my 87 also had the dimples for the clutch master cylinder. I've read that a lot of the later years had the holes drilled out from the factory and a plate bolted to cover them up. Not sure when exactly they started doing it though.

Great write up with tons of detail. Thanks again. I haven't done the swap myself but this lays it out pretty clearly.
 

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Discussion Starter #5 (Edited)
First off, great write up. Thanks for going into so much detail.



Next, my impression is that 97 was the last year for the f250+ with a small block. In 98, the f250 was a "light duty" basically just a 98 f150 with 7 lug axles. As far as I know these had the modular engines. There was no f350 that year. Not sure if there was an f450+ that year and if there was, not sure what engines they had. Also, the 99 f250 and f350 were the super duties which had the modular engines or powerstroke or maybe a v10. They did have the option for a zf transmission, not sure if it was a 5 speed or the zf6, a 6 speed version. At any rate, the modular engines have a different bolt pattern so their trans won't work. Again, not sure about the f450+ in 99.



Next, if you don't want a custom rear driveshaft you can use the driveshaft from a bronco with the m5od. The m5od is the same overall length as a zf5 so both the front and rear driveshafts are the same length on both trans.



Now, about the t-cases. I didn't notice whether you used the bronco or f250 case. The case in the pictures looks like a bw-1356, which was probably the case in both the bronco and the f250 so I guess it really wouldn't matter. Most people use the case originally mated to the zf5 if the bronco and the donor truck had 2 different cases. Not sure why, maybe the crossmember mounts different or it's because the driveshafts would be different. At any rate, the earlier broncos had a different case such as the np208f or a bw-1345. Something for others reading this to keep in mind.



As a note, my 87 also had the dimples for the clutch master cylinder. I've read that a lot of the later years had the holes drilled out from the factory and a plate bolted to cover them up. Not sure when exactly they started doing it though.



Great write up with tons of detail. Thanks again. I haven't done the swap myself but this lays it out pretty clearly.


Updated with correct dates, not sure where I got '99 from. You're 100% correct.

And also yes total brain fart on my part, you can definitely use the M5OD driveshaft from a Bronco. I did tend to find that the only ones I could source were way more expensive than getting a custom one, but you're correct.

I did mention a little late in the write up that I used the F250 transfer case. But bringing that up reminds me that I actually tried the BKO one first (an NP208 IIRC) and while it mated up fine I did end up switching because the driveshafts and shift linkage are a different styles.

Thanks for the reading and the added info!


Sent from my iPhone using Tapatalk
 

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85 Bronco, 309ci I6 w/4bbl, np435, 4" lift, 37" Irok NDs, 4.56 w/ Detroit Locker and tru trac
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The zf5 s42 and s47 were very similar, with the s42 having a torque capacity of 420 and the s47 at 470 ft/ lbs.

Some late model f350s had a BW 4407 transfer case just fyi. It's bigger than a 1356, but similar.

The zf5 came in trucks until about 2002, when it was replaced by the zf6. As stated above, almost everything past 97 will have the MOD bellhousing pattern. They did make the 302 until 2001 or 2002, but i don't think they had a zf5 behind them.

The 98 model year saw leftover 97 f250+s being sold, as well as the new f150 body style. The light duty f250 was just a 150 with beefier suspension and yes, those crazy 7 lug axles. It was also known as the ford 7700, as that's what it's GVWR was set at due to the extra lugs and suspension. I do not believe they made the F-Superduty (ten lug, f450, 2wd) past 96 but I could be wrong.
 

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@tkrone8970 is that slave cylinder the aluminum one? I believe it's the same one I was looking at last night if so. There's no way I'd put a plastic one in there with a billet aluminum one available.
 

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@tkrone8970 is that slave cylinder the aluminum one? I believe it's the same one I was looking at last night if so. There's no way I'd put a plastic one in there with a billet aluminum one available.


I believe it was the aluminum one but it’s a been a bit so don’t quote me. Agreed it’s worth the extra cash to not have to worry about it for awhile. Speaking of which I also wish I had sprung for the BC Broncos braided stainless steel hydraulic line. I’ve read a few cases of the plastic line melting on the exhaust manifolds. Hate to have to dismount the whole tranny just to replace that.


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For the price, I have to assume it was the aluminum one. I never had a problem with the hydro line in my f250 with the stock zf5 and big 460, but I'll probably opt for a stainless one for my swap this winter.
 

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Glad to hear you haven’t had issues with the plastic line. I have headers so I just gotta make extra sure I’m clearing them. Do NOT want to have to take that thing off again haha


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Great thread @tkrone8970 . I swapped my M5OD for a ZF5 some years back. That swap was uneventful but I just had my ZF5 rebuilt and learned a painful lesson that I wanted to share. I think this thread is as good as any of the ZF5 threads, hopefully you don't mind my addition.

When I first installed my ZF5, I had read to use the same year slave cylinder as the recipient truck (1996). I did just that and had no issues. Bleeding the slave was very easy, they essentially bleed themselves. It is the bleeding of a new master / hyd. line that generates all the horror stories out there.

Well I just had my ZF5 rebuilt in Phoenix and as I was buying a new clutch I also ordered a new slave for the hell of it. This time I wasn't thinking and ordered a 1988 slave to match my ZF5. Once I had my transmission bolted in and ready to go, I went to hook up the hydraulic line and realized the connector was not incompatible. Rather than drop the transmission and try to return the slave to Rockauto, I opted to buy a new hydraulic line for $44. The new line attached to my master just fine and plugged into the slave but the hard plastic was routed completely differently due to where it exits the master. This caused me to have to force it into a shape that worked and this made me very nervous. But worse yet, I could not get the system to bleed (or so I thought).

For the next 2 weeks I tried everything I could think of to bleed the system. Gravity, 2 person pump and hold, and removing the mater and line from the truck and stretching them out vertically. Frustrated beyond belief, I resigned myself to the fact I may need to drop the tranny again just to swap out the slave. But, in one last act of desperation I toured my local junk yard and found 2 F-250s with Hydraulic clutches. The F-250 master is significantly bigger bore than the Bronco MC. I theorized in the yard that the F-250 moves a greater volume of fluid and my problem wasn't air at all but volume. $12 later and I had the F-250 MC and line home and installed in my Bronco. It will bolt in but required some redneck engineering. I also ended up defeating my neutral safety switch and I'm not happy about that. But, it all works great now and my pedal is firmer and better feeling than ever. If I have to drop the tranny again someday I'll go back to my Bronco MC so I can have my safety back but for now the truck feels great!

I just wanted to share this story for those contemplating a ZF-5 swap. The morale is....... if you already have a manual, use the slave for your year truck.
 

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@cstrike, are you suggesting to use the slave for a bronco/f150 in your year, or an f250/350 in your year?
 

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I’m swapping a ZF5 into my Bronco from an ‘88 F250. My Bronco is currently an auto. I was planning to buy the complete system from an ‘88 F250. Am I planning properly?


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@cstrike, are you suggesting to use the slave for a bronco/f150 in your year, or an f250/350 in your year?
To be safe I would use the slave for your Bronco/F-150. The bigger 250 masters I found were in older trucks so it is possible that the 250s went with a smaller MC in the later years but by matching the slave to your existing MC you'll know you are good and eliminate that variable.
 

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I’m swapping a ZF5 into my Bronco from an ‘88 F250. My Bronco is currently an auto. I was planning to buy the complete system from an ‘88 F250. Am I planning properly?


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Not sure if that question was meant for me but I would say not to mix and match slaves. The Problem though with sticking with all 88 like I did in my 96 was that the firewall opening was a little different and I had to do a hack job to make it all work. And, the push rod on the 88 MC didn't work with my safety switch. My recommendation is to use a complete system (slave, master and line) from the same year as the recipient truck.

** One important note, although maybe obvious, is that all my experience is limited to small block, concentric slave ZF5s. I can't advise on big blocks.
 

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Not sure if that question was meant for me but I would say not to mix and match slaves. The Problem though with sticking with all 88 like I did in my 96 was that the firewall opening was a little different and I had to do a hack job to make it all work. And, the push rod on the 88 MC didn't work with my safety switch. My recommendation is to use a complete system (slave, master and line) from the same year as the recipient truck.

** One important note, although maybe obvious, is that all my experience is limited to small block, concentric slave ZF5s. I can't advise on big blocks.


My firewall is uncut so I need to make the opening. I’m also installing into an ‘83 which didn’t have hydraulic systems. I guess I’ll try a complete ‘88 system and see how it fits with the pedals I got.


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To be safe I would use the slave for your Bronco/F-150. The bigger 250 masters I found were in older trucks so it is possible that the 250s went with a smaller MC in the later years but by matching the slave to your existing MC you'll know you are good and eliminate that variable.
So what you’re saying is that the slave for a m5od will fit on a zf5? I knew that they can both use the same clutch (meaning you can bolt a 10” clutch from an m5od into a zf5, or a 11” clutch from a zf5 into an m5od) so this kinda makes sense.

And to help with @alfie623’s question, do you think the issues with the 88 f250 master in your 96 was because of the generation changes, meaning would an 88 f250 master fit in an 88 bronco without the “redneck engineering” you had to do?

Edit: looks like you guys hashed it out while I was typing.
 
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