clazer
Newbie
The frame and drivetrain under my 1972 Jimmy are a cut down 1996 GMC Yukon 2 door. The truck runs, but nothing was done cleanly by Dr. Frankenstein, the previous owner. As such, I get to do a lot of reading to figure out repairs. This site has been great, but I can’t figure some things out.
I replaced the front discs with 6 lug 3/4 ton hardware.
Installed all new drum hardware in the rear (it’s an 11” drum 10 bolt).
New master cylinder. Existing vac boost.
I have pulled and bench bled the master cylinder multiple times with the same result: brake gives decent resistance after install. I go to bleed the rear brakes and get no pressure to the rear cylinders. Basically the only fluid that comes out of the bleed nipple is just gravity fed. Then my brakes are soft and just go to the floor. There’s enough to soft-stop using the front brakes, but it’s not driveable.
From what I can tell, the ABS module is there but I don’t see an abs dump valve unless it’s integrated somehow. I’d like to just bypass the ABS module, but none of the guides on here seem to match what I have. What recommendations do you have? Is the abs dump valve already bypassed and the proportioning valve is bad? Something else? Thanks for reading and have a great day!
Also, yes, there’s plenty of other issues in the pics as well, trying to take care of them one at a time!
I replaced the front discs with 6 lug 3/4 ton hardware.
Installed all new drum hardware in the rear (it’s an 11” drum 10 bolt).
New master cylinder. Existing vac boost.
I have pulled and bench bled the master cylinder multiple times with the same result: brake gives decent resistance after install. I go to bleed the rear brakes and get no pressure to the rear cylinders. Basically the only fluid that comes out of the bleed nipple is just gravity fed. Then my brakes are soft and just go to the floor. There’s enough to soft-stop using the front brakes, but it’s not driveable.
From what I can tell, the ABS module is there but I don’t see an abs dump valve unless it’s integrated somehow. I’d like to just bypass the ABS module, but none of the guides on here seem to match what I have. What recommendations do you have? Is the abs dump valve already bypassed and the proportioning valve is bad? Something else? Thanks for reading and have a great day!
Also, yes, there’s plenty of other issues in the pics as well, trying to take care of them one at a time!
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