ScottJ03

How many quarts on GS auto diff for fluid changes...
Thanks in advance. Is 79-90W Redline work?

ScottJ03

timd38

75W90 is perfect. three quarts should do it, no need for modifier.

C7/Z06 Man

Can't go wrong with OEM for your "year" corvette. It has "all" the right additives needed for your GM rear so no other modifiers are needed, that's what I use.

timd38

I changed my diff to Red Line at about 1,000 miles. I then installed a new diff with a Quaife and 3:73 gears, and the inside of the old diff still looked like the day it was built. Also, Red Line had all the additives about three years before GM. In 2006 you did not need friction modifier when you changed to Red Line.

If you a manual trans and change to D4 Red Line, you will see a vast improvement over the OE fluid. I changed mine at 1,000 miles and I have done several other C6s in my garage and the feedback has all been positive. It just shifts better.

I need to make full disclosure. I have been a Red Line use for many, many years and when I retired, they offered me a job, so I went to work for them in January.