I start the next step and i would like Power Brake in my 46 1/2 ton. I found a Brake Booster from our host (for 1947-1954) and now the question: Fit's this in my truck???? with or without modification ? Modification on the Brake Lines are OK but other things?? Volker
Hallo Volker, I put the power booster in my truck. It is very good as far as its response and much less muscle power on the brake pedel. But it still has the old drum system and in a panic stop still takes a lot longer to stop then a new car. The booster was fine to install. I did need to modify the bracket that holds it to the chassis about a 1/4" or so. Be sure to bench bleed the master cylinder. The twin master cylinder was reason enough to install the system. Its a great reassurance to have a twin master cylinder on these hills in East Tennessee. All in all an inexpensive safety upgrade that does not change your trucks originality. Hope this Helps, Chuss! Flashlight
Sorry , No As you have a '41 ~ '47.1 truck there and as far as I know ,the one you're looking at is for '47.2 ~ '54 ADVANCE DESIGN chassis and they're different . I've seen a few AD's with original vacuum assist power brakes , taken off the bigger AD's but I've never done this to a earlier truck like yours and brakes are critical so I won't give bad advice . I do know many have adapted those tiny Japanese vacuum boosters .
Since you said the magic words, "with modification", I'll relay what we have done on several power booster mounts. To preserve the original pedal shaft mounts we take all the insides out of the factory master cylinder and then make a long push rod that runs right through the now hollow stock master cylinder back to the new booster/MC which is mounted on a plate on the frame rail. We use a small Japanese dual diaphram booster for clearance purpose. If the MC doesn't have enough volume for the brake system in use we use the corvette dual MC and whip up an adaptor between the MC and booster. This usually requires a custom pushrod between the booster and MC. Most of the time the Toyota/Nissan/Mazda master cylinder works fine but may not give full pedal height which is fine as long as the pedal is solid. Look for a MC with at least a 7/8" bore. Use a chrome moly or other very tough metal for the brake pedal to booster push rod because you cannot increase the diameter a whole bunch and not rub the wall of the factory cylinder. If the booster is working there is way less strain on the push rod than on a manual brake set up.
modification Thanks. I will go to my local Toyota shop and try to get a new booster for less. ...and will report about my experience with pics ASAP. I hope i won't need a complete brake line system Volker
@ol'chebby i took a look at the internet and found it. They will check and come back if they have the right part for me
Master Power Brakes Ph. # 888.351.8781 They advertize powerbrakes for 1928 ~ 1970 Chevy trucks... OnLine : MPBrakes.com Look at the " Universal under floor pedal kit with Ultra Booster " , PN : PA1502KPO . I hope this works out for you .
I talked with Steve Goddard from MPBrakes and he told me this part works only with automatic trannys. He gave me the measurement from the unit and i will try to find a possiblility to build in. If i have a solution i comeback with pics. Thnaks Volker
" Auto Trannies Only " I think that's because the clearances is tight but I'd imagine you can work up a M/C bracket from the frame......
@Nate I found a way I have to connect (welding) a rod on the original pedal and mounting the booster unit with a new bracket on the frame behind the original brake unit. Then i have more space and if i use a hardened steel rod i can transfer the pedal power to the booster unit. The only problem is i need new brake line (little bit longer). The problem with my truck is the clutch pedal. It's a unit with all 3 pedals and i haven't enough space to mount the brake pedal on the frame. The automatic tranny is easier because i haven't a clutch pedal. Once i have to check: the clearance between the booster and the cabin but i think i will find the best position. If i have it i come back with a picture and i hope it works. Volker
Good Man ! Now you're getting into real Mechanicing ! I'm sure you'll get it . Other than the wretched Huck (rhymes with SUCK) brakes , my old '46 3100 was ideal with just a full pressure 235 engine upgrade , I logged a lot of hard miles on it . it's a wonder those nasty stock brakes didn't get me killed , brake upgrades are a smart idea IMO , I just want to retain the skinny & tall radial LT tires . Carry on and please keep us posted ! .
