Originally Posted By: undertow
Originally Posted By: dailydriver
My T56 actually shifted the BEST with this stuff in it, BUT, everyone on here swears up and down that it just
cannot protect the gears and bearings as well as any thin(ner) MTL, despite their lead tech/tribologist Dave (and his company) claiming the D4 DOES have GL-4 levels of gear/bearing protection.
The T56 in my Commodore shifts great on synth ATF, they don't like thicker oil especially in cold climates. These Tremecs rarely suffer lubrication-related failures even when running on cheap Dexron III ditchwater. Tremec designed them to run just fine without GL4 protection and they seem to have got it right. Most problems with them are people beating up synchros, or catastrophic failures when drastically overpowered, neither of which can be fixed with better oils.
On the Aussie forums, a $70/litre oil is popular to address this non-existant problem, and sells based on "testing" with no control. It's funny to watch the kool-aid drinkers dance around the cold shifting issues that this 75w-80 causes. It's probably a good oil for circuit racing applications, but the price is stupid even by Australian standards.
A heavy duty ATF like D4, Amsoil or Transynd will work well if you want extra protection. GM Synchromesh seems to be a safe choice too, if you don't live in a cold climate.
The Amsoil MTF is one of the thinnest of the non-Euro, FULL synthetic manual trans fluids, and I was going to try it this change (to get the very poor shifting, but proper viscosity, thin, Ravenol out of there).
But I think I am going to just use the D4, as a national champion autocrosser has used it in his VERY high mile (~300K now), beat on, open tracked as well, daily driven, E/Street Prepared Z28's T56 since new, and has NEVER had a problem, or rebuilt the thing yet.
(It's almost $5.00/quart LESS than most of the good, synthetic, MTLs/MTFs out there as well!
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