05 1500hd 4x4 Only Front Wheel Drive Now

SkidooSteve12 · May 24, 2010

05 1500HD 4x4 with 86,500 miles. Ran it in Auto4x4 for awhile yesterday after forgetting to switch back to 2wd. Switched to 2wd about half a mile from my house and as I was pulling in the driveway it just revved up after making the turn. It is a slight incline and the truck just stopped, so I hit the brakes to not roll back into the road. Let off the brakes and gave it a little gas and it revved up again. Tried reverse and same revving up, no go. So I hit the Auto4x4 button and it CLUNKED when engaging and I drove up the driveway. Stopped by the garage and had someone watch the rear driveshaft when I switched back to 2wd, it wouldn't turn in forward or reverse. Let the motor idle down and hit the 4x4 full time button and it clunked in when engaging and the truck would move again. Tried 2wd again and nothing. Went to put it in Park and it started grinding like crazy! Put it back into Neutral, let it idle down and hit the Auto4x4 again, it clunked again, but didn't grind when I put it in Park.

Decided to drop it off at the dealer I bought it from today because of convenence to get an estimate.

Anyone have any ideas to the issue??

Thanks!

Dooner · May 24, 2010

Sounds like a transfer case issue to me...Let us know what the dealer says.

SkidooSteve12 · May 24, 2010

Right, obviously the transfer case is only working for the front driveshaft now. I am wondering if there is a solinoid or switch that could have gone bad which is used to engage the rear driveshaft in the transfer case? Could the truck be acting like the transfer case is in Neutral? That is what I'm hoping it is and nothing wrong with the guts of the transfer case....

Yeah I'll keep everyone posted on what the dealer finds out.

SkidooSteve12 · May 26, 2010

I got the call at 6:00 PM, truck is done already. It was a combo of binding linkage, debris in the oil, and then a bad encoder motor sensor I think it was. So after straightening the linkage, cleaning the inside, and testing the bad sensor and replacing it the bill was $393.01 which is a lot less than I was expecting!

They first checked the linkage by hand I guess and it wouldn't work, so they opened the case and found some debris in there. They suspect that the case was opened up before, but can't tell for sure. So they cleaned the pump and case, straightened out the binding linkage, and filled it with fresh oil. Then after it worked by hand, they put the encoder motor back on and the sensor for that was not testing correctly, so that was replaced and it works fine now.

I did ask about the known problem with the pump retainer breaking and letting the pump move around and wear a hole in the side of the case but was told that was not specifically checked. He was going to check with the mechanic to see if it was checked but not noted on the repair report. I'd feel better knowing that was checked... but without the updated retainer kit installed, I will just have to periodically check the TC for oil stains since it mostly leaks while driving and doesn't drip down while parked.

Dooner · May 26, 2010

That sounds awefully cheap for all that work. I'm guessing they had to remove the transfer case form the truck to open it up correct? Sounds like you got a good deal to me. Glad your ride is back up & running.

jro909 · May 26, 2010

was that a dealer price?! if it is you made off like a bandit damn..

SkidooSteve12 · May 26, 2010

Yeah this was at a small town Chevy dealer that's 35 miles from my house, with about 3 or 4 other Chevy dealers closer. My family and my wife's family have been doing business with them for over 25 years, so I'm guessing I got the repeat customer discount. I haven't seen the bill yet, but from doing more searching specifically on the encoder motor sensor I have found other similar conditions where the 2wd has quit and needed 4wd to move the vehicle. The one post I read said the linkage could still be moved by hand without the encoder motor in place, so not sure why my linkage was binding, but with buying a used vehicle you never know what was done to it previously. Looks like if you just replace the sensor at home it should be under $100.