Everyone thinks I'm nuts (maybe they are right ) but I change my rear fluid every 10K miles and my tranny too. Cheap insurance for a $50K car was the way I saw it, but this thread makes me feel even better about it. I am using Amsoil though. I know the Redline is good oil, and the rear oil especially gets rave reviews over on Bobistheoilguy.com, but I have always been concerned about seal swell with the ester base that Redline uses.

 

A line-lock is a electrically operated device that holds the front wheel brake pressure during a burn-out, (which keeps the car from moving while spinning) while letting the rear brake pressure release completely eliminating drag to prevent damage to the driveline and rear brakes.

Also, changing the oil in the diff is a breeze. You'll need a 10mm allen socket and a siphon/filler tube, both of which you can find inexpensively at your local Sears store.

 

Thank you for this very valuable info.

 

How can a differential cooler be added without removing the differential? Where should the cooling lines go?

 

For those of you that plan to add a differential cooler~ Be sure you return the cooled oil back into the differential at the TOP of the differential, rather than back into diff. via the filler hole. There is an informative thread we posted to here about a month and a half or so regarding that, which will be some good reading before you add that cooler. I'll try to find it and post the link here...

EDIT: Found it~ http://forums.corvetteforum.com/show...ler&forum_id=1

If you insist on returning the oil back to the diff. via the filler hole, make *ABSOLUTELY* sure you fill the entire unit completely full to capacity, (diff, cooler hoses, fittings, pumps, etc, etc.) otherwise you'll damage the differential due to running it too low on oil. We've seen it many times....

 

is the royal purple 75-90 good stuff? that is the only thing i could find in a hurry.

 

We really don't want to stir up a debate on oil because that's been done here on this board to infinion and it's a *BIG* can of worms.... The six oils we tested back then was Redline, Royal Purple, Amsoil, GM, Lucas and Mobil 1.

What we will say is that the Redline oil faired the best in our tests I described earlier and has continually proved the test of time by being installed in literally hundreds of DTE differentials all over the U.S. and abroad with outstanding, long-term mileage success. Based on that proven track record, we recommend Redline.

Hope that helps a bit.


Best Wishes,
Phil- DTE

 

Red line, done deal.

Randy

 

Phil,
Which AMSOIL gear lube did you use in your test, they have two grades, and both have been recently reformulated?

Not trying to stir the debate, downplay the quality of Redline, or take away from the original point of the thread, but for those that prefer a non-ester based synthetic gear lube (AMSOIL is PAO based), I have been using the AMSOIL Severe Gear Extreme Pressure Synthetic 75w90 for SCCA T1 racing and my stock diff has lasted over 15k miles, 9 DE events and over 25 SCCA races.

 

How much fluid fills the diff. tank?

 

Without having the files in front of me, I can't remember what type of Amsoil it was. That was three years ago now and I can barely remember my name sometimes...!

Getrag differentials take 1 bottle of LSA and just shy of two bottles of gear lube.

 

DynoTech
I don't want to start a big debate so I will ask the ? here. What Manuel Trans fluid would you recommend ?

 

We have always used Redline MTL in all of our HP manuals.

 

whats the difference between ester and pao based? i dont know what either of these terms mean.

 

This is quoted from a website called lube-tips.com. As a note, AMSOIL synthetics use a PAO base, but do have an ester additive (along with other anti-wear and detergent additives) for the reasons mentioned below. Redline synthetics use an ester basestock. The below also discusses the downsides to switching and why a flush may be advisable.

"Generally, the reference to synthetic oil for an engine, means a lubricant is formulated with a polyalphaolefin (PAO) base oil. PAO, which is often called synthesized hydrocarbon, is pure and is compatible with mineral base oils.

However, because the PAO base oil does not dissolve additives effectively, it is usually formulated with an ester co-base (usually di-ester and/or polyol ester). The additives are soluble with the ester and the ester is soluble with the PAO.

Likewise, the PAO tends to cause seal shrinkage and the ester causes seal swelling, so the effects are offset when both base oils are present. It is the ester that can cause problems when one changes from mineral to synthetic. Ester base oil used alongside PAO base oil in lubricant formulation has excellent natural detergency. In other words, it will clean up varnish on component surfaces as a result of thermal and oxidative degradation of the lubricant. When one switches from a typical mineral-based engine oil to a typical synthetic-based oil, the varnish layer will be removed by the ester in the synthetic oil and become suspended.

This suspended material can rapidly clog filters and can block oil flow passageways and lead to component starvation. The same is true for gearboxes and other industrial machines. So think twice about switching to synthetic oils in applications where the engine or other machine has been operating for some time with mineral oils. If you decide to make the switch, try to clean the system before making the change, then monitor it carefully once you start it up."

Rob,
Stock diff takes just under two quarts.

Thanks Phil.
Both the AMSOIL Severe Gear Extreme Pressure Synthetic 75w90 (preferred for the Corvette) and the AMSOIL Long Life Synthetic 75w/90 Gear Lube were reformulated late last year to meet the increasing demands of differentials in modern cars and trucks (smaller capacity, higher heat, less airflow).