Front differential clicking - repair options

[alvocado]

My 2011 GMC Yukon with 216k miles has developed a clicking noise coming from the driver side output of the front differential. It sounds like tire noise while driving so I pulled the wheel and disconnected the CV axle at the diff, spun the diff flange and the noise was confirmed to be the differential. I've done 50k mile gear oil changes so the gears should be in good shape. Despite being very mechanically competent, I don't have any experience rebuilding a differential. 

 

For those with experience, is this likely the output shaft bearing and is it worth finding a driveline shop to rebuild vs. sourcing a used assembly? I'll have to pull the diff out myself and drop it off if I go the driveline shop rebuild route and will be down for a week waiting on parts after the shop tears the assembly open. 

 

I did have a GMC dealer rebuild a front diff on a Yukon about 14 years ago but I doubt they see many of those jobs.

[Jsdirt]

I'd wager it's probably something to do with the engagement portion of things. May have ended up partially engaged, and is skipping over the splines.

 

However these are the weakest differentials ever produced, so anything is possible.

[alvocado]

I didn't think the gears were engaged if the truck is in 2WD (not auto mode), only the output shaft rotates because it's attached to the CV axle. If just the shaft is moving, I would think it's a bearing. I did cycle through full time 4WD mode but no change. 

Edited October 17, 2024 by alvocado