Prob scrambling for a job as there will be no one to Uber for weeks

 

So, back with an update. Happy to say I finally fixed it. Here are the deets since last time: The GM service writer actually brought in her 01 L200 and had the tech actually swap master cylinders so we could see if an OEM MC made any difference. It did not. So swapped them back. At the end of the day, they had no answer. She only charged me for the original factory service pressure bleed of the abs system. The remainder of the trial and error was on their dime. So they really did try and help me out but they just didn't have the answer. They suspected that the only thing left was the brake booster, even though they knew I'd replaced it...TWICE. But the OEM version is no longer available from GM so no point in having them replace another one...they'd be getting aftermarket just like what is on it. So brought it home and as a last resort, I ordered a used OEM unit off a working 03 L200. I thought maybe the OEM version is actually different than what the reman units are. Sure enough, put the old unit on it today and the pedal is FINALLY back where it used to be years ago. So here's what I think transpired in the series of events that started all this: Master cylinder originally went sneakers up and I replaced it after bench bleeding but did not realize the abs pump needed a pressure bleed. This caused problems even after the MC was replaced and I started going down the list of the "usual suspects". Replacing the booster was part of that. Replaced it with aftermarket and that's where things apparently went south. I think if I had known about the pressure bleed after MC replacement, and had left the orig booster alone, the problem would have been solved years ago. There is apparently something inherently different about the OEM boosters. It works beautifully now, especially given everything else brake-wise on the car is brand new.

 

Glad you finally got it repaired.

 

Thanks for letting us know. I was wondering what in the hell we could have all missed.