Differential fluid change questions

[y2kz71]

I have a 2000 Z71 with the 4.10 locking gears. I am going to change the fluid front and rear but I need to know how many quarts to buy. I have done a search and found that I need to buy three quarts of synthetic 75w-90 for the rear (measure during re-fill to gm spec). However how many quarts of the regular gear lube should I buy for the front. Also what type of gasket sealent should I use for the rear if any. Any help will be appreciated. Thanks.

 

[Frank S]

I don't have a fullsize so I can't give you the amount but if you look in your owners manual,it should list the exact capacity.

For the gasket sealer,just get some non hardening of form a gasket.That's what I used on my rear differential when I changed it and it works fine.

[y2kz71]

Well believe it or not, I have checked the owners manual and it does not have the fluid capacity for the front or rear. It just says to fill it within xxxMM from hole. I was thinking about using RTV sealant or some guys say none at all, just the gasket. I just don't want to be right in the middle of this and not have enough fluid, or with the price of synthetic (?.00/qt) have too much fluid.

[Frank S]

I had trouble finding my differential capacity in my owners manual at first as well but,and I'm not saying you're wrong,I'd be thouroughly surprised if it isn't there.

I don't think mine was listed under regualr capacities and I didn't think it was there at first either but after i dug through a lot of stuff,i found it.

[RyanbabZ71]

the capacity is in the owners manual.  I forget where i dont have it handy.  The rear diff takes like 2 and a half quarts.  Front???

 

[Frank S]

If the rear takes 2.5 quarts,then the fron is like 1.75 because that's what my capacity is in the rear and I knot the IFS differential is going to take less than the SRA differential.

[y2kz71]

Yea I knew the rear takes about 2-1/2 qts, but I can't find about the front. The book tells more about driving drunk than servicing your drivetrain!

[MountaineerTom]

I think mine only took 2 quarts in the rear diff when I did mine a couple months ago.  I'll have to check it again to see if it's up to the level it should be.

[hiside3]

My service manual says 2.1 quarts for the 8.6 inch Ring Gear, and 3.5 Pints for the Front Axle. Hope this helps.

[y2kz71]

Thanks everyone, I guess I need to break down and buy a service manual. My original owners manual does not give the capacities for this. Thanks again!

[hiside3]

Just a warning for ya. I got the GM service manual, the one you can order from the back of your owners manual. It was something like ? and is 4 volumes, each as thick as a phone book. That's because 90% of it is diagnostic computer stuff and made for both the Chevy and GMC pickups and Tahoes and Yukons. I'm still gonna look for a Chilton book.