Tell your so called mechanic to keep on replacing parts...Sooner or later he'll get lucky.
Also tell him to figure out what the TCCM is, where it is, how to pull codes from it, and how to clear those codes. Then look at the encoder motor...That'll cost about 200 clams unless he's crazy enough to get it from the chevy dealer..and about another 200 clams to install it..
Thanks for your response. The mechanic that I brought my Jimmy to is very reputable. I have been going to him for years and he has always treated me fair.
When I first brought the vehicle to him I am certain that the dash switch was broken. That was only a $35 fix. However the vehicle still would not go into 4WD high after replacing the switch. When the button on the dash was pushed for 4WD high you could hear the motor attempt to put the Jimmy into 4WD but it just wouldn't go. It would, however, go in and out of 4WD Low without a problem.
The mechanic then told me that he thought that it was the actuator motor But I may have misunderstood him and maybe he meant the TCCM. Anyway, He called the Chevy dealer and got a price of $579 fot the part alone. He than called a 3rd party supplier who gave him a price of $289 for an aftermarket part. He put that part in my car but still no 4WD. He told me that after he replaced the motor, it worked for 2 or 3 times and then stopped working again. He then put my old part back in and told me that I should bring it to the transmission specialist but he thought that there might be "something going on" inside the transfer case. He didn't charge me a cent for his efforts.
I will be the first to admit that I know nothing about 4WD or how it works. I want to get this car fixed but I don't want to "mortgage the farm" in order to do so. I plan on bringing it to a transmission place but don't want to be "taken to for a ride". I am looking to find out ahead of time what the problem might be and how much I can plan on speding to get it fixed.
One last note. The 4WD worked flawlessly when I last used it, but that was last spring and never used 4WD again until 2 weeks before Christmas when I discovered that I had a problem.
Again, I really appreciate your help and truly value your input.