Rough Shift in Auto but not 2HI

[JGarver574]

I have a 2014 Chevy Tahoe LTZ, purchased as a used certified from Chevy Dealer. 120k miles. A couple months ago, I started feeling it shifting rough, and a slight rubbing noise when turning and accelerating while turning. This is my wife's car and she always runs it in Auto mode because I don't trust her to turn the 4HI off in the winter when pulling into her parking garage at work. When I put the truck in 2HI mode, all shifting and rubbing problems go away. I can't do that permanently though, as I live in Indiana and have to have 4WD.

Where should I start to look as the source of problem? Any help is much appreciated.

 

[wjburken]

I have a 2014 Chevy Tahoe LTZ, purchased as a used certified from Chevy Dealer. 120k miles. A couple months ago, I started feeling it shifting rough, and a slight rubbing noise when turning and accelerating while turning. This is my wife's car and she always runs it in Auto mode because I don't trust her to turn the 4HI off in the winter when pulling into her parking garage at work. When I put the truck in 2HI mode, all shifting and rubbing problems go away. I can't do that permanently though, as I live in Indiana and have to have 4WD.

Where should I start to look as the source of problem? Any help is much appreciated.

First off-Welcome to the forum from Iowa.

I usually suggest folks only drive in Auto4WD when conditions warrant it. 90% of the time your roads in Indiana do not require anything other than 2HI. I live in Iowa so have the same kind of weather. That being said, I would look at your front differential actuator to see if it is disengaging properly. From what you are describing, your vehicle is locking into 4HI all the time when in Auto4WD.

 

[JGarver574]

First off-Welcome to the forum from Iowa.

I usually suggest folks only drive in Auto4WD when conditions warrant it. 90% of the time your roads in Indiana do not require anything other than 2HI. I live in Iowa so have the same kind of weather. That being said, I would look at your front differential actuator to see if it is disengaging properly. From what you are describing, your vehicle is locking into 4HI all the time when in Auto4WD.

Thanks, I’ll read more about how to do that. Unfortunately, I just don’t trust my wife to remember to move the truck in and out of 2HI. I’ve tried, and she’s called me saying she almost wrecked because she was in 2HI in a snowstorm.

I had no clue that Auto was not good for it all the time. I figured that was like my AWD cars where it just put power where it needed to go all the time.

 

[wjburken]

Thanks, I’ll read more about how to do that. Unfortunately, I just don’t trust my wife to remember to move the truck in and out of 2HI. I’ve tried, and she’s called me saying she almost wrecked because she was in 2HI in a snowstorm.

I had no clue that Auto was not good for it all the time. I figured that was like my AWD cars where it just put power where it needed to go all the time.

Driving in Auto4WD is a source of controversy here. There are some who say you should only drive in it when you have the chance of coming upon some bad road conditions. There are some that say you should be able to run it all the time regardless of road conditions. I’m of the school that you should use it when you need it but that’s just my opinion.

At the end of the day, your system appears to operating like it is in 4HI even when it’s in Auto4WD. We just need to figure out what’s going on.

You have two points of engagement for your 4WD. Your transfer case and your front differential. The fact that you are getting some bucking while turning would lead me to start by looking at the front differential as it seems to be locking the two axles together. Check the actuator and make sure it’s actuating. Would be best if you have a bi-directional scan tool like a Tech-II for this, but with the vehicle safely on jack stands you should be able to see what’s going on.