Quote:
Originally Posted by The Tony Show  103k? Take it in and have the clutch bled several times- sounds like you've got either air in the line, low fluid or no fluid in there. While you're at it, have the trans flushed and filled with Dexron VI (factory fill was the older Dexron III). |
Dexron VI is not recommended by GM for the Tremec manual trannies. The correct GM fluid is GM part 88861800. Here is a cut and paste from a Tech Bulletin on the subject:
"Manual Transmission fluid part number 88861800 U.S. (88861801 Canada) is currently available through GMSPO. Current and past model vehicles listed above with either a manual transmission or transfer case that REQUIRE Dexron III should use the above listed manual transmission fluid. This fluid is a direct replacement for Dexron III in manual transmissions and transfer cases. DO NOT use Dexron VI in place of the manual transmission fluid in any manual transmissions or transfer cases as a failure may result."
I believe that GM found that the Dexron VI had viscosity too low for Tremec Manuals and came out with the new part number which is essentially just a re-issue of the older Dexron III.
The
AMSOIL ATF (stock code ATFQT) mentioned above was reformulated to lower its viscosity to make it suitable for Dexron VI applications. After I brought up the issue of Tremec applications with AMSOIL they changed their primary recommendation for Tremec trannies to the
AMSOIL Torque-Drive Synthetic Transmission Fluid (stock code ATD1G).
The basis for this change was that the Torque Drive (ATD) has a viscosity nearly the same as the original Dexron III (7.41 cSt at 212F for the ATD) whereas the ATF had been reformulated down to a viscosity of about 6.8 cSt, nearly as low as Dexron VI which is about 6.5 cSt. Additionally, the Torque Drive has no viscosity modifiers so is absolutely shear stable, whereas the stock Dexron III fluid's basestock shears down very quickly. As an example, I drained my stock fluid at 10,636 miles and the factory fill Dexron III had sheared down from a nominal 7.3 or so to 5.03 cSt. Ouch. I can only imagine what the OP's tranny fluid has sheared down to after 100k miles.
I drained the AMSOIL ATF I had put in at 10k miles after about 6k miles of use and its viscosity remained at 6.85, exactly what it had started at. I replaced the AMSOIL ATF I had in my tranny with the AMSOIL Torque Drive ATD at that time. Although the ATD has a little higher viscosity than the AMSOIL ATF, I really didn't notice a difference in feel.
All that said, for AMSOIL fluid users, AMSOIL's website now shows that the ATF has been reformulated again, is no longer recommended for Dexron VI applications and its viscosity is up to 7.6 cSt. This appears to be positioning it for primary use as a Dexron III application, leaving AMSOIL without a product for Dexron VI applications right now. However, as I don't know how much of the Dexron VI version of the AMSOIL ATF they have in their warehouses, I'd still recommend the AMSOIL Torque Drive ATD for those wanting to try AMSOIL tranny fluid.
