Transmission problems with 2004 z71 Tahoe

[jyates1959]

Well,

Just traveled 950 miles to come and see my son and family for the Christmas break and about half way out here I noticed that when I was going down hills that the transmission was going out of gear and I would have to slow down and it would "shift" back into drive. It went from going back into drive fairly quickly to not wanting to shift back into drive. So I pressed the auto 4 WD button and it went into drive and never slipped out again.


Tried it on the street once I got into the city and sure enough with it set to 2 WD within a couple of blocks it slipped out of drive and wouldn't go back in until I pressed the auto 4 WD button.

I checked the transmission fluid but it looks to be between the hash marks on the dipstick.

Is this a transmission problem or tied to something else?

It's a 2004 Z71 Tahoe with about 120,000 miles on it.

Thanks in advance for any help!

 

[Wake]

Never heard this one before. But the fact that it stays in drive when the auto 4WD is engages makes me think it has to be the transfer case. Nothing else IMO that it could be. If it was the trans then it wouldn't care if you were in 4WD or not.

 

[scottg918514]

I would replace the tc encoder motor: http://www.rockauto.com/catalog/moreinfo.php?pk=2194984&cc=1424247. Sounds like the tc isn't engaging the rear drive shaft in 2wd.

 

[jyates1959]

Here may be another clue.


I just remembered I noticed that there was an orangeish yellowish indicator light drawing of an engine on the dash when we got here today. And after parking the Tahoe for a few hours when I got back in it the symbol was gone and the Tahoe was taken on about a 5 mile drive in town and it never dropped out of gear. I had driven it around the neighborhood when I first got here and the indicator light was on and it wouldn't make it 2 blocks without it dropping out of gear.

Correlation between light and the dropping out of gear?

I may be wrong, but when I push the AUTO 4WD button I don't think it's actually in 4WD because I can put the Tahoe in neutral and push the 4WD button and hear it lock into 4WD and when I pull forward or make turns you can really feel the difference. Plus, with the AUTO 4WB light on I was driving interstate at 75mph or more and I think if it was actually in 4WD at that time.

 

[scottg918514]

Here may be another clue.


I just remembered I noticed that there was an orangeish yellowish indicator light drawing of an engine on the dash when we got here today. And after parking the Tahoe for a few hours when I got back in it the symbol was gone and the Tahoe was taken on about a 5 mile drive in town and it never dropped out of gear. I had driven it around the neighborhood when I first got here and the indicator light was on and it wouldn't make it 2 blocks without it dropping out of gear.

Correlation between light and the dropping out of gear?

I may be wrong, but when I push the AUTO 4WD button I don't think it's actually in 4WD because I can put the Tahoe in neutral and push the 4WD button and hear it lock into 4WD and when I pull forward or make turns you can really feel the difference. Plus, with the AUTO 4WB light on I was driving interstate at 75mph or more and I think if it was actually in 4WD at that time.

On the last part, the auto 4wd engages the front drive shaft, but doesn't transfer power to the front, unless slip is detected.

 

[Bergy9]

Our 2005 the transfer case would do the same. Ours the lights on the 4wd buttons would change as well. I changed the transfer case shift motor as mentioned above & no problems since.

 

[jyates1959]

Thanks for the information gentlemen. I assume it's okay to just run it in 4WD Auto until I can get back home and get it repaired?

Is replacing that motor a big deal that a semi handy guy can't do or is it best to carry it to a mechanic or transmission shop?

 

[jyates1959]

Is replacing the transfer case motor a big deal that a semi handy guy can't do or is it best to carry it to a mechanic or transmission shop?

 

[scottg918514]

Won't be easy without a lift, but doable.

http://youtu.be/1PPf2Yzhjmw

 

[jyates1959]

Thank goodness for a father in law with a nice shop and a lift!