Differential Service

[JUSTWUFN]

Getting ready to service my rear diff on my wife's 2004 Yukon. I have read as many of the posts on here that I can find and I have a few questions.

Noticed that some of you guys have mentioned using magnets to check for metal debris in oil. Does the factory install a magnet in the differentials to catch the metal or you guys using your own magnet to check for the metal debris? I assumed you were using your own magnets to check for shavings once oil is drained. Am I right or wrong?

Also, silicone vs gasket. What do the service techs use at the dealer?

Is there a DYI section on the site that lists suggested steps to do the diff service?

 

[HankHill]

My factory cover had a magnet on it. I believe you'll find yours does, too. Gasket vs. RTV? You'll get all kinds of answers on this. I used a gasket. Truth is, either way done right will be fine; and done wrong they'll both leak.

As for a how-to, I'm sure they're out there on various sites & youtube, probably.

Here's some of my personal advise:

if you live in the rustbelt or if the cover looks rotted, replace it. You can get a kit from the dealer that includes new cover, bolts, and gasket. The new cover includes a magnetic drain plug for future changes. It's not that expensive. I like the setup, and I primered & painted mine flat black.

For the refill, buy or make a funnel with a hose attachment. It's easier to pour in the new fluid that way.

Torque the bolts with a torque wrench.

Good luck!

 

[91RS]

The differential uses a paper material gasket that is a little difficult to clean off (but easier to clean off than RTV), but hardly ever leaks. If you do buy a gasket, get the GM one from a dealer. I don't know if parts stores offer a differential gasket, but if it is a crap rubber or cork gasket like what comes with an aftermarket transmission filter kit, it will leak.

 

[rhinom67]

You may want to upgrade your fluid other than factory. Just make sure its compliant. Royal Purple or Lucas