Quick Brake Booster Upgrade

[goathearder]

So the 73 I bought recently has 35's on it and leaves quite a bit to be desired in the braking realm. The last 4x4 I owned was a jeep XJ and on those you could swap in just a booster from a later model jeep and significantly increase braking power.

Is that something we can do on the K5's? I have seen some threads talking about 3/4 ton and 1 ton boosters but no real specifics. Anything that could help me brake better would be awesome!

 

[bot0611]

Are you sure your braking system is fine, no air in the system and your actuall booster is in ok condition, the hose from where it sucks vacuum is ok and the grommet on the booster side is ok...

I changed my booster to a stock brand new one like 3 years ago and it brakes just fine, i run 33's but with more weight that a stockish truck, id say checking the actual system might be a good idea if you havent done it already, ive been told a car brakes up front first due to the weight of the engine, i guees its true so...

 

[goathearder]

Yea, I checked the whole system and its functioning fine. It brakes the way I expect a big truck to brake but I can't lock the wheels and on something without ABS I should be able to lock the wheels. I am sure it cause of the larger tires, same exact thing I experienced with my old XJ. Added 33's and couldn't lock the tires, added a larger brake booster and could lock the tires again.

I see a bunch of talk from the Pre-73 guys about the 1 ton booster but not much from us 73-91 guys. Is that mod only viable for them?

 

[1BEATK5]

hydroboost. problem solved.
they arent difficult to install, can be cheap if you are good at scrounging, and offer alot better braking ability.
all 1 tons, and all diesels from 73-91 had it. so not too hard to find

 

[owenst7]

The stock braking system is more than enough when it is working properly. My '76 is running a new OEM system and I can chirp my 40s if i so desire. I have a feeling something is not working 100% on yours. I do not have hydroboost either.

 

[goathearder]

Well that is interesting to know. If it can lock 40's then 35's should be no problem. I'll have to run some more diagnosis.

 

[1BEATK5]

I can lock my 39's with 4wheel discs in my 6000lb k5. with the stock booster and 3/4 ton master cylinder. i prob should have mentioned that earlier

 

[owenst7]

I'm also still running drums in the back. Suppose that makes a difference.

Really, this class of vehicle is meant to tow to some extent. The brakes are pretty forgiving relative to smaller vehicles.

Obviously there's lots of variables and your mileage may vary, but these trucks have way better brakes than the jeeps I wheel with. I ride shotgun with a group of xjs when I'm broke down semi-frequently. They're running 32s-33s and cannot lock the tires up on steep descents, even with well maintained stuff/aftermarket parts. So I would say that you should experience relatively better braking with one of these trucks.

 

[goathearder]

I am thinking i should probably do a full flush on the brake fluid. I have no idea the last time the previous owner did that.

 

[bot0611]

I can lock my 39's with 4wheel discs in my 6000lb k5. with the stock booster and 3/4 ton master cylinder. i prob should have mentioned that earlier

Whats the diference betwwen the 3/4 ton and the 1/2 ton master cylinder? aint it the same thing?

Yeah bleed the system first, make sure it doesnt have any air in it and test again