Changing Differential Oil Question

[wes335]

Is the correct part number for the 10 bolt rear differential gasket 15807693?

And is there a drain bolt on the front or do I need to get a gasket for that one as well?

[MS3DALE]

There is a drain plug on the front.

I can't remember if thats the correct number or not,I'd have to check once I get back to work Monday.

[dlstewart01]

http://www.gm-trucks.com/forums/index.php?showtopic=98116

[wes335]

Ok thanks, two more questions...

1) Am i going to have to remove the skid plate to get to the front diff?

2) Does the rear take about 2.5 quarts and the front 1.5?

[thearborbarber]

You are correct. Mine took a little less than 2.5 in the rear and a little more than 1.5 in the front.

[wes335]

And can both rear and front use 75w-90 with no limited slip additive?

[Westlotorn]

If you have limited slip you must use an oil with the additive or you can purchase the Limited slip additive at your local parts store and add it to your oil.

 

A gasket is optional on the rear diff, you can replace it with Silicone, have both the cover and the diff clean and ready to close it up. Make sure no oil is dripping down to mess you up.

Apply a very thin coat of Silicone to the Differential and place the cover on. Be careful to not let it slip at all while you do this or you may wipe off the silicone. Start all your bolts and bring the cover up tight slowly and as eavenly as possible by working the bolts in a pattern. The factory used silicone for years as do most shops. Silicone is flexible and seals over less than perfect surfaces.

 

Fel Pro is a gasket manufactuer that puts out a very high quality Diff Gasket. They are available at almost all parts stores if you choose to go that way.

 

Good luck.

[MS3DALE]

You do NOT have limited-slip....Do NOT use any additives.

[MS3DALE]

And can both rear and front use 75w-90 with no limited slip additive?

 

Yes,You do not need any additive.