I have a 98 GMC Sierra K2500 P/U 4X4 @165,000, automatic tranny, with a 454. When I brake sometimes a noise is made and sounds like the ABS pump only super, super loud, more like a chattering. Sometimes it sounds like it is coming from the right side of the truck and sometimes from the left. I can also usually feel the noise in the steering wheel. Then right after brake release, sometimes it makes the noise and it feels like the brakes aren't fully released. I also have a howl during very light breaking. It has new hubs because I thought it was a bearing problem, but that didn't stop the noise. The rotors were turned and new pads installed and it stopped for a day, then started again. It also has new ball joints because I thought that could have caused it. Nope, still makes the noise. I have tested the ABS and it works fine. I really am leaning towards calipers or master cylinder. Other then that, I am stumped. I also have replaced the rear shoes, bearings, seals, and wheel cylinders. Anyone have the same problems that I am having?
Did you find out what it was? If so would you mind passing me your knowledge as I have something similar although not the same. Tks ian iantan@talktalk. Net
March, 2, 2008 AT 11:46 AM
Ian, I found out what the problem was. It was the tranny. It had too muich oil pressure on it when it was trying to shift from first to second and vice-versa. It was causing the tranny to chatter in between shifts. I went ahead and bought a GM Goodwrench tranny and it was fairly easy to install and it took about 8 to 10 hours.