1988 k1500 NO power brakes help!

[Grant Henderson]

My grandpa bought this truck new in 87, it basically has a manual brakes at this point. I want to fix it. The brakes are terrible and very unsafe.

It would probably be easier to tell you things that have been replaced than things that haven’t: (all new)
3 different brake boosters
3 different brake masters
Brake calipers (both sides)
Rotors
Pads
Wheel cylinders
All brake hoses
Most brake lines
Proportion valve

The truck has been at his mechanics shop for the past 4 months. I have not had a chance to do any diagnostic work myself.
I have been told that the the booster is getting vacuum and that the brakes are worse the the vacuum line plugged (I find hard to believe). Any input would be appreciated. I want to actually diagnose the problem, I am very tired of all of this parts changing

 

[Rusty_Lewis]

Sounds similar to my faulty ebcm. Maybe its worth a check

 

[Erik the Awful]

Rear brake adjustment is critical in getting the brakes working good on these trucks. I'd verify that first.

If you took it to the mechanic and asked him to "fix the brakes" and he's thrown all these parts at it without fixing it, he needs to fix it for free.

 

[Grant Henderson]

Rear brake adjustment is critical in getting the brakes working good on these trucks. I'd verify that first.

If you took it to the mechanic and asked him to "fix the brakes" and he's thrown all these parts at it without fixing it, he needs to fix it for free.

The mechanic has actually done all the work for free and feels terrible about the whole situation. I’m not blaming anyone just want it fixed.

 

[Grant Henderson]

Sounds similar to my faulty ebcm. Maybe its worth a check

The abs as been deleted

Sounds similar to my faulty ebcm. Maybe its worth a check

The abs has been deleted.

 

[dave s]

Could you possibly have the incorrect brake rod? When I switched my old Nova to 4 wheel discs I discovered there were a couple spots on the pedal where you could connect the brake rod. I'm just throwing it out there, something like this is hard to figure out without actually seeing it. And is he sure he got the correct bore size master cylinder? Wish I could be more help.

 

[Grant Henderson]

Could you possibly have the incorrect brake rod? When I switched my old Nova to 4 wheel discs I discovered there were a couple spots on the pedal where you could connect the brake rod. I'm just throwing it out there, something like this is hard to figure out without actually seeing it. And is he sure he got the correct bore size master cylinder? Wish I could be more help.

It’s not impossible, I work At orileys and I was looking at the masters and the are 2 diffrent piston diameters. I assume they would have matched them up when the put the new one on but I’d be lying if I said I knew for sure. Thanks.