Questions about brakes on a 1969 k5 4x4

[draggin49]

Just picked up a 69 k5 blazer 4x4 . Took it for a drive , runs great , but the brakes are awful to the point of dangerous. Barely any stopping power and don’t engage till pedal damn near is touching the floor.The booster on it is stamped remanufactured , so I’m guessing the master cylinder is as well . Just debating on if I should even bother going through messing with this setup or just replace it with a fresh one . If I replace it I want to use something that will be a direct replacement for what’s in there and not require a bunch of other changes or mount location etc .

[notsolo]

Best to pull each wheel/ brake drum and check condition, wheel cylinders brake pads etc. Decent replacement booster and master cylinder are probably not easy to find....nice looking Blazer BTW.

[draggin49]

Thanks for the input I will take it by my buddies shop and we can pull each wheel and assess how things look. I figured an original brake /booster in good shape would be super hard to find so I can live with a reproduction unit if I can find one that’s just like the one in there so it’s an easy swap . Appreciate the compliment on the blazer ! I had been wanting a mostly original one to daily drive , and this one popped up . It’s a solid vehicle overall , no major rust anywhere and original paint is weathered but presentable .

[hemi43]

Some things should not be kept original especially drum brakes if you plan on driving this on public roads. Do a disc swap so you can actually stop like modern cars.

[1970cstblazer]

There were a couple of things that I absolutely hated about driving my 1970 Blazer. One was the accelerator pedal that would fall off if you looked at it cross eyed, and the other was the front drum brakes. The braking effectiveness was mediocre at best, and more often times than not the thing would pull to either side. During the restoration, I have addressed both. Both designs were updated to 1971/72. Should not be hard to convert it over. The parts are still plentiful and will solve your poor braking.

[draggin49]

I’m cool with upgrading to disc brakes if it’s an easy swap . Car will see daily driving use so power disc brakes would be worth doing .

[notsolo]

I agree with upgrading to disc brakes, didn't want to suggest changing out original parts. I have no experience with 4x4 drum brakes up front. Those with similar trucks can possibly suggest compatible axle swap or kits to get it done. GM 6 lug axles were used thru the 80's..I tried a Classic industries booster master combo....looked wrong, tilted down and leaked....my better choice was 3/4 ton booster and master cylinder from 83-84 Chevy 1500....disc / drum combo. Works well...Good luck.

[hemi43]

I made my own disc brake conversion for my70 and still retained the 70 axle and hubs. It was a fairly easy swap, but some fabrication/machining is required.

[jaros44sr]

While your in there

I would strongly recommend a hydro boost, it will put you into the windshield, if you’re not careful

Brake lines tend to rust, I went with braided SS, and ni cop tubing, easy to work with

I can takes of my stock brake components as a guide for what you need if it helps

[hemi43]

Originally Posted by jaros44sr

While your in there

I would strongly recommend a hydro boost, it will put you into the windshield, if you’re not careful

Brake lines tend to rust, I went with braided SS, and ni cop tubing, easy to work with

I can takes of my stock brake components as a guide for what you need if it helps

It will put you in the windshield when the engine stalls and you slam into the wall.
Hydroboost should only be used on diesels and boosted engines IMO.

[jaros44sr]

Originally Posted by hemi43

It will put you in the windshield when the engine stalls and you slam into the wall.
Hydroboost should only be used on diesels and boosted engines IMO.

That’s what you got emergency brake for, all else fail go cable

Good point though didn’t think of that

[litebulblsc]

Hydroboost has an accumulator that still provides boost when the engine is turned off. Vacuum boosters also rely on the engine for power. You can usually get a pump or 2 from vacuum booster, but more from the hydroboost.

If hydroboost is good for diesels then it us just as good for gas engines.

[franken]

Some swap the diff with a disk setup of a late year with the same ratio.