We have an '02TB with the flaky 4wd/2wd selector system.
When the TB is at higher speeds (40 mph or above) and it magically jumps from 2wd to 4wd, we just switch it back to 2wd and all is well again, no noise, no thumps no nothing, it just shifts. When it jumps into 4wd, the TB doesn't handle any different, steer any harder, or sound any different.
Now, when we are going very slow, especially when pulling into a parking spot or driveway, many times it will jump from 2 to 4wd. Everytime we switch it back to 2wd, the TB makes a loud thud or thump as it goes back to 2wd.
The wealthy PO had a GM installed new TCCM and a new encoder/motor.
Any ideas on where to start, or what the thump is?
Thank you,
Joe
(I'm not a newbie to cars/trucks at all, just to the TB)
When the TB is at higher speeds (40 mph or above) and it magically jumps from 2wd to 4wd, we just switch it back to 2wd and all is well again, no noise, no thumps no nothing, it just shifts. When it jumps into 4wd, the TB doesn't handle any different, steer any harder, or sound any different.
Now, when we are going very slow, especially when pulling into a parking spot or driveway, many times it will jump from 2 to 4wd. Everytime we switch it back to 2wd, the TB makes a loud thud or thump as it goes back to 2wd.
The wealthy PO had a GM installed new TCCM and a new encoder/motor.
Any ideas on where to start, or what the thump is?
Thank you,
Joe
(I'm not a newbie to cars/trucks at all, just to the TB)