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Discussion Starter #1
Asked that question in another thread, but it may have been not the right place for it as it got no responses - I see my brake booster is mounted to the firewall with a funky bracket, and there are 4 bolts that hold the booster to the bracket, will it be possible to yank a booster off an F350, and bolt it to my current bracket I have? I sure seems easier than crawling under the dash with flex joints and extensions trying to get the bolts for the bracket off the firewall. Next, once I've acquired the F350 booster, will my F150 master cylinder bolt to it? I just put a new one in there, besides the F350 lines come out on the wrong side of the MC anyways. Reason for all that is that my truck usually stops nice as is, but sometimes I kinda run out of vacuum assist and have to lean on the brake pedal as if it got manual brakes. Thanks!
 

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It's useless to do an F-350 upgrade without replacing the M/C with a 350 M/C. The booster unbolts from the firewall bracket and the 350 booster bolts on the same exact way. The lines are very simple to bend around to the driver side and if you replace one of the lines (don't remember if it was the front or rear line) going to the proportining valve all you need to do is buy a 3/16" to 1/4" adaptor. The adapor will screw in the PV and then screw the new line in the adaptor.

The 150 M/C has a smaller bore than the 350 M/C does so I would advise upgrading your M/C.
 

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Do a search, this subject has been "beat to death"

In summary:

Use the M/C and booster from the same year as your truck.

Bend your brake lines to fit, it is not hard.

You will need to replace the rear brake line flare fitting, the F350 is different.

Many report issues with rebuilt auto parts store M/C and boosters....beware.

This mod works best with T-bird brake calipers up front, but the mod requires lots of plumbing.

Good Luck
 

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Discussion Starter #4
Yeah, unfortunately the chances of finding a '78 F350 in the junkyard are slim to none. I'll look tho, juts may get lucky. For now I'm planning on just swapping the booster out, I ain't afraid of running brake lines (had my whole Chevy redone for hydroboost and manual prop valve, worked sweet), tis just too damn cold to be doing anything major like that. Once the temperatures reach the point where my skin don't try to get fused to the metal of the wrenches I'm going on a brake line replacing spree, I'll be redoing every single one in the truck - at that point the F350 master cylinder will be installed too. Thanks for the info tho, makes the picture a whole lot clear :D
 

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Exactly arch. Send your old stuff back as a core. And reconditioned is the way to go. If it malfunctions they will gladly replace it. This is not something to get out of a junkyard.
 

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Discussion Starter #9
only thing is the new brake booster is over $100, and the MC another like $50 or so - tis a sheer financial issue, not that I don't want a new booster, I just can't afford it right now. On another note, did Ford ever use hydroboost? Like the GM 1-tons?
 

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I used a F250 master cyclinder and a F-150 manual brake assembly for my brakes. no power assist and I like it that way
 

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Discussion Starter #13
I used a F250 master cyclinder and a F-150 manual brake assembly for my brakes. no power assist and I like it that way
How did that feel, did you have to lay on the brakes a lot? I had stock manual brakes on my Chevy, they were okay with undersized tires (245/60-15), but were pretty weak with the regular truck tires (235/75-15) and flat out sucked with the big 32/33s. Did you run big tires in your truck at the same time as the manual brakes?
 

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Discussion Starter #14
Pretty sure they did.
So what vehicles am I looking for as donors for the hydroboost? All F350s I've seen have been vacuum assisted, maybe a diesel truck will have hydroboost? If I get the Saginawesome pump then tis easy, I can just run GM stuff all the way (I have one laying around), but then I still will have to mate the GM line to the Ford steering box... Ideas, suggestions?
 

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Discussion Starter #15

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The only hydro-boost units I'm aware of came on the mid/late '70's BIG Ford cars (Mercury Monarch, Ford LTD, etc). You probably need the matching master cylinder from that year, as there are a few different units available from the rebuilders. Stay away from the GM units with the internal accumulator - they don't work really well with big tires.

http://www.partsamerica.com/ProductDetail.aspx?MfrCode=A1C&MfrPartNumber=527078&PartType=250&PTSet=A

If you're looking to do good brakes on a budget, I don't see how you'd want to try plumbing up a hydro-boost system. You're going to get eaten alive with pressure hoses (you need two of them), and most sources recommend swapping in the Saginaw power steering pump with twin return lines. You're looking at a lot of parts.

And don't forget the cardinal rule of hydraulic-assisted brakes: if you frag your ps pump out on the trail - you just lost steering AND brakes.
 

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Discussion Starter #17
Actually the GM units I'm talking about are from 3/4 and 1-ton trucks (both diesel and big-blocks), and look exactly like the one you pictured for the fullsize Ford cars - well, different mounting plate, but the rest looks the same. The booster in my Chevy was from a 3/4 diesel Suburban and wokred awesome for the big tires, truck would stop so fast I scared the heck outta one of my friends during a panic stop on the freeway - but I guess that booster I had ain't the one with the internal accumulator. As far as pressure hoses go - j/y Saginawsome pump, hoses for the GM booster, the GM booster I got now, and a fitting from Russel or somewhere to mate the GM line to the Ford box. Actually if the Ford box uses a 3/8 flared line I can just cut lines and swap nuts, then reflare - that's what I had to do for my Chevy, as the box and pump wanted flared line but the hoses had o-rings. It can be done on a budget, just gotta have the right parts supply and tools for the install. You do have a great point about the pump and the trails action tho...
 

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IMO hydroboost especially the GM ones are a horrible joke. I was a tech in the military and did several swaps because the saginaw did not have enough shit too it to run both the brakes and the steering in a hard stop or hard steer. (considering this particular rig had 4 wheel steering) I don't think I've seen a unit that didn't leak, besides all the extra plumbing which just adds for more leaks down the road. Also another thing to consider If I was doing this kind of swap I would also add more cooling to the system. I can see trail use cooking those systems pretty interesting. If it were me, I'd stick with vacuum. Anyways just my 2 cents
 

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I've dealt with so many leaks in the 1960's/70's era power steering systems, that I decided that adding a four foot pressure hose, a 20-30 year old hydraulic booster, and an extra return line is just asking for trouble out on the trail. When I think about plumbing in a cooler as well - oooh that makes my stomach hurt...

If you look outside the diesel applications (which obviously NEED the hydraulic booster), few factory hydraulic boosted brake systems have been successful. I think that speaks to the ability to engineer a system that will provide long term service and reliability.

The most likely way a vac-assisted booster will fail is with loss of engine vacuum. That's pretty unlikely while the engine's running normally. A hydra-boost can go anytime there's loss of fluid pressure - which may or may not telegraph itself ahead of time. Do you really want a braking system that can fail while you're flying down the trail?
 

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Discussion Starter #20
That's some good points for sure, guess vacuum it is then - my engine pulls 19" at free idle and like 17" while sitting at a light, so should be good. About hydraulic booster systems being unreliable tho - old models yes, they are notorious for springing leaks, but right now damn near every GM truck, van, and SUV has hydraulic boosters, they gotta be halfway good then, right?
 
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