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351m / 400 transmission & TC options

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#1 · (Edited)
351m / 400 transmission & TC options (chose ZF-5 + Dana20)

I have done quite a bit of reading over at FTE but wanted to post up here as well as this forum is a bit busier (more active) so might get more eyes on.

I have about had it with the NP435, love the granny gear but hate just about everything else. Shifts like a bag of hammers, clutch takes the hulk to engage (centerforce clutch?), gearing is spaced out like half of Colorado and while I could probably live without the overdrive I do quite a bit of highway miles, enough that it would make a difference to have it.

I know my options are pretty limited considering I will need a transmission that has the big block bolt pattern while trying to keep the rear driveshaft as long as possible.. this is on an early bronco by the way. I love the granny gear, would like to retain that either through the transmission or transfer case. Overdrive.. half the reason i would like to do this swap.

Keeping a manual transmission what are my options, what about transfer cases?

EDIT: Decided to go with a ZF-5 out of a 460 truck and use the adapter to retain the Dana 20. I will keep this thread updated as my build thread too :)

I'm currently leaning toward a big block zf-5 (some machine work and fab envolved) with either the $$$ adapter mated to a D20 or an $$$$ atlas... I know the np205 mates directly to the zf-5.. but the length!
 
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#2 · (Edited)
C-6 would be the easiest swap for an auto but no OD. ZF would be another option and not a hard swap. E4OD would be a PITA but not impossible. You would have to use a stand alone computer set up.

A 205 is not that long of a case and I think the D20 is same mating pattern? Not to sure about the input spline count?
 
#3 ·
No auto for this rig, keeping the manual.. plus this is on an early bronco (69) never get the e40d to fit without a stretch and I don't think it will fit between the frame ;)

Dana20 requires an adapter to mate to the zf... I think it runs close to $700 - I'm on my way to an atlas at that price...

NP205 mates right up to the zf but its heavy and makes things even longer.. every inch counts as they say especially on an early bronco.

I need to take some measurements, but to check my boxes I think the zf is the only candidate. I have been reading a few threads of guys who have adapted it to the 351m/400 and there are quite a few hurdles and machined parts to make it work correctly... not afraid just want to do it right!
 
#4 ·
I thought it was as simple as pulling a ZF out of a 460 truck and it would bolt right in? Not doubting you on the adapters because I have never don it. What issue are you having with the NP 435? I like mine a lot in my wheeler and I know Ogeechee has had good luck with his even on the road. I know its not a trans your going to speed shift gears with but not sure what you experiencing.:thumbup
 
#7 ·
The bolt pattern is the same however there isn't enough spline engagement so you have to have a Custom pilot bushing machined A few have done it with no problems.. just a matter of getting it done right. There are a few other issues such as the flywheel and starter spacing etc..

I'm just not a fan of the NP435.. shifts like rocks, heavy HEAVY pedal, gears are really far apart and although with the 400 its probably less noticeable than a smaller engine.. it just adds onto the pile for me. Also I drive quite a bit on the highway.. I need that OD... but want to keep the granny if possible. I drive my bronco allot.. not just for wheeling so headed toward making it more "road friendly"


Its very odd that someone put an M block into an EB. Usually every one uses a 302 or 351w. Then you would have all kinds of choices.:doh0715:
Tell me about it.. but its what i have and its fuel injected and its a torque monster.. less than 1800 miles on a total TM rebuild so I will live with it for now :)

I don't think a E4OD would work in a EB

the ZF would be the way to go it is lighter and within a inch of the NP435 4x4 version

if your 435 is of the 2wd flavor with that dana20 it be pretty hard to get to that shorter length

you more then likely have a three finger clutch if it is really hard to push
go with a diaphragm version and you will enjoy pressing the clutch pedal

I thought you could get a OD unit for a Dana20 Tcase
I can't see an E40D being installed on a stock length early Bronco.. I dont want the heat issues either.. the 400 is enough!

Even if i throw on a different clutch or go hydraulic.. its still going to behave the same way.. I would rather solve most if not all the problems and be done with it :)

Same goes for the OD for the dana20.. just a bandaid, would rather just replace and checkoff most of my boxes, was just wondering if there were any other options for transmissions..

I will have to go take some more measurements, I know i can do it and will loose some rear drive shaft length, but I can make up an inch or so by moving the rear axle back and sticking with a TC case solution that will keep the length down...
 
#6 ·
I don't think a E4OD would work in a EB

the ZF would be the way to go it is lighter and within a inch of the NP435 4x4 version

if your 435 is of the 2wd flavor with that dana20 it be pretty hard to get to that shorter length

you more then likely have a three finger clutch if it is really hard to push
go with a diaphragm version and you will enjoy pressing the clutch pedal

I thought you could get a OD unit for a Dana20 Tcase
 
#9 ·
#12 ·
Well i have been reading about the NV4500, and it seems like a great transmission but also seems like a more expensive route to take. It looks like I can use the NP435 bellhousing with an Adapter plate.. plus a few other bits and pieces to get it to mate to a d20.. or suck it up and go with the 205..

Besides the expensive and the problem of finding one cheap.. I have found out the following about the NV4500

The bellhousing pattern is the same for the 400 and 460 but the 460 bellhousing is a 1/2 inch or so longer. If you put a NV4500 on a 400 bellousing with an Advance Adapter kit you will need to trim the input shaft and bearing retainer a little for a proper fit.

Requires special very expensive transmission fluid, I guess only available from a GM dealer.

5th gear nut likes to back off..

Lots of adapters and thats going to cost allot of money...

good news is, its short ;)

I will keep researching. I have not really found a definitive article talking about an actual install onto a Ford 400 but only looked tonight.

I can pickup a big block ZF-5 for $89 right now.. haven't seen a Dodge NV4500 under $1700.. but haven't been looking too hard.

It's a long shot, BUT......................

Back in the late 70s, early 80s, Ford used a version of the Mopar 883 4 speed, with 4th gear changed to an OD gear. If you can find one for a 4x4 application, there ya go.
I will do some research and see what I can dig up.. i found a Clark 5 Speed for sale.. but wrong bolt pattern and don't think it has the .73 final drive.

put in a hydraulic clutch
I was going to on the NP435.. but will probably wait until I install the new transmission. No matter what I go with I will install a Hydraulic clutch with slave. The big bolt pattern ZF has an external setup.. I think the NV does too.

no matter what transmission you use the clutch is going to behave the same

3 finger requires extra effort to disengage regardless of transmission

diaphragm requires less effort to disengage regardless of transmission

since this is a conversion you may have your linkage in a bind causing even more effort to work the clutch
I think your right as the clutch rod that goes through the floor and attaches to the clutch lever on the frame is kind of hacked on (PO) .. not happy with the angles. Honestly I could live with the heavy pedal if i wasn't unhappy with the gear ratios, hard shifts and lack of OD.

I understand the NP435 is not a race car trans.. i know its tough, and like i said I can see the appeal for most trail rigs but its just not for me :)

plus this gives me another excuse to work on the Bronco!

Thanks for the ideas guys.. i will keep on researching, its part of the fun.
 
#11 ·
no matter what transmission you use the clutch is going to behave the same


3 finger requires extra effort to disengage regardless of transmission

diaphragm requires less effort to disengage regardless of transmission

since this is a conversion you may have your linkage in a bind causing even more effort to work the clutch
 
#17 ·
Well I see you already got your Trans but I've been researching an OD swap for my 78. I'm going with an AOD. A couple companies I've found that make a bellhousing for it. Cut the old one off the housing and bolt this one to the pump bolts. I'm leaning to this route. With an EB would probably be the best size for your rig.


Sent from AutoGuide.com App
 
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#27 ·
Interesting reading......

I would love to see a pic of your engine bay. I have never seen a engine such as yours sitting under the hood of an EB. Fuel injected to boot- WOW!!

Please Post a pick or two, if possible.

Gonna follow this thread to see the outcome. I like the "IDEA" of overdrive as well as you. However there arent many options to keep your transmission/tranfercase from kissing your rear axle.:popc1:
 
#32 ·
More than that...I count about 5 of us with 400s in EBs.

mine is TBI, with Aussie heads.
Well thats a first. I am sure that you have enough power in your rigs with those engines. I never would have guessed that there was enough clearance for exhaust,or little things like, steering shaft, bell housing, and such. I know that the tunnel must be modified to get one of those 4 speed trannys in there. How do you keep them cool? Very little room in there for a fan and a radiator- even with factory engine. I have a 400 in my fulsize and there is plenty of power to pull my RV. I guess that you need very little pressure on the skinny pedal to pull ANY hill.
I installed a 351W in mine and ran into problems with throttle and had to clock my hydroboost to get it in there. No motor mounts to modify
 
#35 ·
mine is MPFI, with Aussie heads... yadda yadda yadda.. no york :(

Ignore the hairy hand, big foot was in my garage.

and the paper filter is gone.. have replaced it with a higher quality one...





Found a badge too.. dont tell the 62 Galaxy guys...



Only fitment problem so far.. custom oil pan.

 
#37 ·
Landshark
Look like there is plenty of room with your stock manifolds in place,for steering shaft, Column, linkages. I am truly amazed at how well the engine tucks in the bay. Go ahead- you guys idle up a hill while I downshift:cry

After installing my hydroboost from Manual brakes the first time..... I pulled out of the garage and almost hit my head on the winshield. Utter disbelief that so little pedal pressure was stopping the truck. My wife climbed in for a drive and depressed the pedal so hard (like she was used to) that the powersteering pump whined, I quikly told her that it needed just a Big Toe to stop the vehicle. We both had to re-learn how to drive it as well..
 
#44 ·
I'm adding MPFI to my '78 Bronc's 400. Right now its still carbed. It's a new engine, with a roller cam, built Aussie heads, one of my custom intakes like the one in the pic, and "i'm not yet sure which" throttle body. Something quite similar to the one Jope's built before he became ghey and quit wheeling. :goodfinge

I have to use the single planes for those custom MPFI intakes and they are only available used.

The 400 in my '69 EB is TBI (Commander 950) and it works just great, so no plans to change that. I even bought a second identical system to install on the fresh 400 in FordFilly's '79.
 
#45 ·
You could go with the Accufab TBs or the 90* elbow and run a factory style Ford TB on it... personally I like the look of the 351W GT-40 adapted with the Price Motorsports adapters, though. I think there is an engine overall height advantage with using a carb intake for the injection. My upper plenum is very close to the lip on the firewall.
 
#46 ·
so a little progress and decision making..

i decided to sell everything and get a honda






























of course iam kidding.. but i did pick up the zf-5 today...

Length of the zf-5 is 26.25"





My spacer is also ready and I will be picking that up tomorrow.. and then.. figure out the adapter for the Dana20..
 
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