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Posted

Mine is pretty loud and obvious that the 4wd is working when I have it engaged. Even if auto I still have the transfer case noise going on, I think it's normal. Do you have a SLT or SLE? I find when I drive my Dads SLT its much quieter than mine which is an SLE. The SLT more than likely has more sound deadening in it even though the interiors look the same.

Posted

The Dealership installed everything on my truck and I have a signed document stating that they will still stand behind factory warranty.

Man you got much cooler dealers than I do up here! Lucky!

Posted

Man you got much cooler dealers than I do up here! Lucky!

They are pretty awesome! I took it in because I was having some vibration issues at 70 mph(more than there should be). They replaced all 4 tires(35x12.50x20) and fixed the problem. They also gave me a 2013 Yukon Denali for a loaner. Thing only had 10 miles on it!! As a bonus they have a theatre with like a 100+" screen in the waiting room!!!!!

  • Like 1
Posted

I've had my truck for about 6 weeks, so it has very low mileage still (about 1400 miles), but there is definitely a little extra audible noise when driving in Auto or 4Hi. It's due to the front diff being engaged. I'd say the sound is "normal", but that's me. I'm not a GM service department, but I suspect they'll tell you the same.

Posted

Hi TYLERZ7180,

 

I understand that you are experiencing problems with the Automatic 4WD in your vehicle. I am glad to hear that you are taking your vehicle to your dealership. Please let us know if we can further assist you with your concern. If we can be of any assistance, please send us a private message.Thank you.

 

Kristen A.

GM Customer Care

  • 2 months later...
Posted

Do NOT use auto with this sytem. I've replaced 3 issues in transfer cases on my 2007-2013 Tahoe while using auto. My wife thinks it means exactly what it says, but it is not intended that way according to GM. I've had it at 3 dealers now and they say always use 2WD for day to day, and only auto when you will be in 4WD conditions.

 

Spent thousands so far learning the transfer case is not designed to be driven in auto all the time.

Posted (edited)

 

 

The Dealership installed everything on my truck and I have a signed document stating that they will still stand behind factory warranty.

Are you really expecting an answer other than "NORMAL" ? :lol:

Edited by pm26
Posted (edited)

Do NOT use auto with this sytem. I've replaced 3 issues in transfer cases on my 2007-2013 Tahoe while using auto. My wife thinks it means exactly what it says, but it is not intended that way according to GM. I've had it at 3 dealers now and they say always use 2WD for day to day, and only auto when you will be in 4WD conditions.

 

Spent thousands so far learning the transfer case is not designed to be driven in auto all the time.

 

 

This is correct. Don't use auto unless needed. In regular dry driving situations. 2hi is fine. using auto all the time is just going to wear things out faster.

Edited by fondupot
Posted (edited)

The only vehicles that are designed to remain in auto 4WD mode all the time are full time 4WD cars and trucks.

Edited by pm26
Posted (edited)

The part that isn't rated for constant duty is the ball bearings in the control actuator lever. - Its the part that actually applies the clutches in the TC. 340018d1393791517-mp3024hd-transfercase-

The balls are 13mm (0.512) in and should be made of a hardened steel. - GM went cheap on this part and they degrade. Jeeps run the same case that is constant duty with the hardened ball bearings.

Edited by chrisuns
  • 2 months later...
Posted

Uggghhh...well mines going to the dealer tomorrow AGAIN!! This makes me sick to my stomach!

I had this as well (Stock z71 LTZ). GM sent an engineer up here to take a look as there were several from my local dealership having this issue. After the engineers report was sent to Detroit they replied with "It's due to a square chain in the transfer case (instead of rounded) creating 'noise,". And decided not to do anything about it. Good thing I have a good relationship with my dealer as they went the extra mile... had me take a fresh of the hauler z71 for a weekend to see if the problem existed on that truck as well. After driving it for the weekend and determining it did NOT have the vibration issue my dealer swapped my transfer case out for the one on the newer truck. Problem solved... but don't expect anything from GM themselves. I tried working through their customer assistance line and got nowhere. Your best bet is finding a dealer that will take the time to work with you.

Posted

I had this as well (Stock z71 LTZ). GM sent an engineer up here to take a look as there were several from my local dealership having this issue. After the engineers report was sent to Detroit they replied with "It's due to a square chain in the transfer case (instead of rounded) creating 'noise,". And decided not to do anything about it. Good thing I have a good relationship with my dealer as they went the extra mile... had me take a fresh of the hauler z71 for a weekend to see if the problem existed on that truck as well. After driving it for the weekend and determining it did NOT have the vibration issue my dealer swapped my transfer case out for the one on the newer truck. Problem solved... but don't expect anything from GM themselves. I tried working through their customer assistance line and got nowhere. Your best bet is finding a dealer that will take the time to work with you.

 

So they actually changed the transfer case design part way thru production....so much for consistency.

Posted

 

So they actually changed the transfer case design part way thru production....so much for consistency.

I don't think they actually changed the design (yet, at least)... I just think there is a big enough difference for certain tolerances on the internal parts. So two trucks off the same line on the same day could have some internal parts from a supplier that are on opposite ends of the tolerances and one could exhibit the behavior and might not. Just a theory from dealership and so far I have been satisfied with the swapped TC.

Posted

I don't think they actually changed the design (yet, at least)... I just think there is a big enough difference for certain tolerances on the internal parts. So two trucks off the same line on the same day could have some internal parts from a supplier that are on opposite ends of the tolerances and one could exhibit the behavior and might not. Just a theory from dealership and so far I have been satisfied with the swapped TC.

 

I know my truck is considerably "noisier" in auto and 4hi, but I don't use it enough to complain.

Posted

 

I know my truck is considerably "noisier" in auto and 4hi, but I don't use it enough to complain.

Yeah, mine was so bad I could feel it in the floor boards and the steering wheel, and my passengers could feel it in their feet as well. Now it seems more like you are describing yours, "nosier" but tolerable.

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