04 Suburban front Differential Noise

[Tonino]

Hello All. I'm reading where the front differentials on 4X4 Vehicles with the AWD option can be troublesome. My 04 Suburban Z71 4X4 w/AWD has a noisy front differential.
Its akin to a rhythmic scraping noise. If anyone has had a rebuild, would that be a bearing or a gear? 135k miles on the odometer and serviced about 1,000 miles ago. No metal shavings or chips came out with the fluid. Other than that, the truck is a delight. Thanks for listening.

Tonino

 

[rockola1971]

Hello All. I'm reading where the front differentials on 4X4 Vehicles with the AWD option can be troublesome. My 04 Suburban Z71 4X4 w/AWD has a noisy front differential.
Its akin to a rhythmic scraping noise. If anyone has had a rebuild, would that be a bearing or a gear? 135k miles on the odometer and serviced about 1,000 miles ago. No metal shavings or chips came out with the fluid. Other than that, the truck is a delight. Thanks for listening.

Tonino

The front diff is the same on a 4wd and AWD other than the extension housing that bolts on. My 05 Denali is coming up on 300K and its all original. Your scraping noise sounds like a bearing. I would get it in the air and rotate by hand and see if the exact area can be determined. The front and rear diff is not a job to learn on. It requires an actual setup to get correct engagement of pinion and ring gear. Measurements inlcude to the thousandths of an inch and torque spec with preload. It really is an art.

 

[Tonino]

The front diff is the same on a 4wd and AWD other than the extension housing that bolts on. My 05 Denali is coming up on 300K and its all original. Your scraping noise sounds like a bearing. I would get it in the air and rotate by hand and see if the exact area can be determined. The front and rear diff is not a job to learn on. It requires an actual setup to get correct engagement of pinion and ring gear. Measurements inlcude to the thousandths of an inch and torque spec with preload. It really is an art.

Thank you Rockola. I'm in agreement. No way am I qualified to do a differential. I've heard about the precision tolerances required and I do not have those hand skills. I was toying with just having the bearings replaced if the noise was indeed bearings but once its down, might as well go remanufactured with a reputable source and get a decent warranty to *****. The guys in the trades know who the best sources are and I will rely on the recommendation of the shop that handles all the care and feeding of my truck. i'm new to the group. Thank you for your learned wisdom.

 

[Fless]

Check out those wheel bearings while you have it in the air. Might not be the diff.

 

[Tonino]

Check out those wheel bearings while you have it in the air. Might not be the diff.

Thank you Fless. I haven't had the truck very long. Will do a sanity check on the wheel bearings next tire rotation, ck them off the list one way or another. I had the drive line listened to with a stethoscope and the verdict was the front differential. Transfer case, rear differential were quiet.