Rear end fluid change help

[FirehawkNS]

I did a lot of searching on a couple of boards for the last 30 minutes and I am having trouble getting the info I want.

I plan to change the fluid in my rear since I want to test and see if it will help with all the loud noise that is coming from the rear. I can't really describe the noise, but it is kinda like a da..da..da...da..da...da..but kinda in a exhaust gargle (but not) sound. Does it when accel or deccel, but not all the time, just most of the time. Anyway, What I want to know is

1. What kind of fluid? How much fluid(I think I heard 3 quarts or something)? I think I have a torsen, but I don't know how to find out. It is a 99 Z28.

2. How do I change the fluid? I saw a write up on installuniversity, but that includes replacing the cover. I just want to drain and refill. Do you drain and refill with the aftermarket cover the same way with the factory one?

3. Should I take off the cover and see what everything looks like in there? Since it is making noise and all!! Can you just reuse the factory gasket, or do I need to buy another once I take the cover off?

I think that does me. Thanks for any help!!

[Tranzor_Z28]

First, you should have a Torsen since you have a '99 Z28... now to your questions. ;)

1. The rear end will take almost 2 full quarts of fluid... I used Redline 80w140, but you can get away with any synthetic fluid of 75w90 grade. But I still recommend Redline...

2. If you have an aftermarket diff. cover by T/A, then it has a drain hole at the bottom of the cover itself. If you still have an OEM cover, then you'll have to take the cover off.

The refill hole is on the passenger side of the diff. You will have to use some sort of flexible funnel in order to get the fluid in there. Keep filling until it starts to run out of the hole.

3. Taking the cover off is a good idea if you're really worried about what it looks like in there. Otherwise, it is not necessary if you have a drain hole in the cover. And I wouldn't reuse the factory gasket, just get a new one.

[FirehawkNS]

That sounds like the ticket man!! Thanks