I have a random but frequent mechanical noise coming from the front driver side of my 98 Yukon. Its like gears winding up and down when driving, but not grinding. I took a picture, and there appears to be fluid coming from the driver side flange port. Is this worse then a bad gasket? Thanks ahead of time.

Picture of the leak

The seal is fairly easy to replace because you can unbolt tha axel and get it out of the way but with the growling noise I would be suspicious of the bearings in the diff. I would drain the oil and look for metal debris.

The fluid leaking out is clean, just changed it 6 months ago. If there are shavings, I'm looking at a rebuild? I used Mobil synthetic 85-135ish. I checked the boards, should have been fine. Maybe 80-90 is better.

As very good possibility your side gear bearings are worn. Usually when this happens no shavings are found, but the fluid will have a glitter look while shining a light on it.

Hmm, interesting. I will try to look at the fluid tonight. From what I can tell, this is a K1500 front diff (correct me if I am wrong). Just trying to research what I rebuild would take in terms of time, if i have to. Thanks again.

yes everything is the same as a k1500