Driveline BANG in 4X4 mode

[Audioi]

Have a 2014 Sierra 5.3 Auto 4X4 with 30k on it. Recently I have used 4x4 auto going up a hill and heard/felt a loud bang from the driveline. Anyone have info on this?

[ftwhite]

If it was possible that one of your rear wheels lost traction, you might have felt the rear diff lock up. It throws out a little latch when speed between the left and right changes, and locks up the rear wheels. Can be abrupt.

[JimCost2014]

On 2/19/2021 at 8:23 AM, Audioi said:

Have a 2014 Sierra 5.3 Auto 4X4 with 30k on it. Recently I have used 4x4 auto going up a hill and heard/felt a loud bang from the driveline. Anyone have info on this?

Like the above post said, you will hear things when parts engage under load.

 

Can you describe the conditions of the road when you heard it?

[Audioi]

Both times it was uphill, once on dirt the other on a snowy drive.

[JimCost2014]

4 hours ago, Audioi said:

Both times it was uphill, once on dirt the other on a snowy drive.

I would say it was a normal noise, thinking you lost traction each time and the AUTO4WD kicked in at speed. All it takes is a 100 RPM difference between the wheels and the G80 locker engages, not sure on the front wheels.