You bring up a number of interesting points. I am not going to read all of the comments on some other blog, but will attempt to respond to some of your comments.
A. My information on the paper/cellulose blocker rings on the 1998-2000 Tremec T56 manual transmissions is that they are actually blocker rings of kevlar/graphite/cellulose composites, similar in composition to the clutch disc material in Allison AT's.
B. The Tremec series has always been, in my view, a problem child with respect to fluid specs. In some cases, they speced this fluid, while in other cases they spec a different fluid, supposedly with the same internals. Why? My guess is they found that, with their original specs for the higher viscosity fluids, shifting was poor in cold weather, so they dropped the viscosity and at that point in time, the only available fluid with a low viscosity was ATF - which is no longer the case.
Why weren't other fluids, such as Pennzoil Synchromesh (9.3 cSt), and other slightly higher viscosity fluids tested? My guess here is that they had some design problems, either due to shifter clearances, or due to cluster gear shaft clearances.
C.
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At B. 5 on the list of MTL's GM's Manual Transmission and Transfer Case Fluid is listed. From what I've read, this is merely rebranded ATF (no license renewal on the old stuff), probably to satisfy the need to say they have what you require.
The fluid mentioned (GM product (#88861800)) is basically a Dexron III(H) fluid with additional AW levels of a phosphate/anti-oxidant chemistry.
D.
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Others have tried Synchromesh, synchromax, RP, Amsoil ATF, etc. with varying degrees of success. I read a number of blogs describing T56 failures using the higher grade MTL's in the pre-2001 models. I don't recall reading about any failures/problems associated with DEX III, Mobil syn ATF, or the GM MTL.
And most of these comments had no definitive cause-and-effect details as to why the trannies failed. Did anyone have their trannies examined by a competent transmission shop and a determination made of the failure? Was the cause of failure due to an increase in engine HP via performance chips, was it due to tracking not covered by warranty, was it due to inadequate maintenance, U-joint vibration, transmission mounts? What?
When we were blending, marketing and supplying customers with our own versions of MTF, including a low viscosity MTF (called "MTFGlide," 7.5 cSt (75W80)), and MTL-P (MTL Purple, 11 cSt, 75W85)) customer feedback showed no problems with the Tremec series of transmissions. These fluids had the same AW additives and friction modifiers as did our 75W90 MTF called MTL-R (14.5 cSt, MTL-red).
A. My information on the paper/cellulose blocker rings on the 1998-2000 Tremec T56 manual transmissions is that they are actually blocker rings of kevlar/graphite/cellulose composites, similar in composition to the clutch disc material in Allison AT's.
B. The Tremec series has always been, in my view, a problem child with respect to fluid specs. In some cases, they speced this fluid, while in other cases they spec a different fluid, supposedly with the same internals. Why? My guess is they found that, with their original specs for the higher viscosity fluids, shifting was poor in cold weather, so they dropped the viscosity and at that point in time, the only available fluid with a low viscosity was ATF - which is no longer the case.
Why weren't other fluids, such as Pennzoil Synchromesh (9.3 cSt), and other slightly higher viscosity fluids tested? My guess here is that they had some design problems, either due to shifter clearances, or due to cluster gear shaft clearances.
C.
Quote:
At B. 5 on the list of MTL's GM's Manual Transmission and Transfer Case Fluid is listed. From what I've read, this is merely rebranded ATF (no license renewal on the old stuff), probably to satisfy the need to say they have what you require.
The fluid mentioned (GM product (#88861800)) is basically a Dexron III(H) fluid with additional AW levels of a phosphate/anti-oxidant chemistry.
D.
Quote:
Others have tried Synchromesh, synchromax, RP, Amsoil ATF, etc. with varying degrees of success. I read a number of blogs describing T56 failures using the higher grade MTL's in the pre-2001 models. I don't recall reading about any failures/problems associated with DEX III, Mobil syn ATF, or the GM MTL.
And most of these comments had no definitive cause-and-effect details as to why the trannies failed. Did anyone have their trannies examined by a competent transmission shop and a determination made of the failure? Was the cause of failure due to an increase in engine HP via performance chips, was it due to tracking not covered by warranty, was it due to inadequate maintenance, U-joint vibration, transmission mounts? What?
When we were blending, marketing and supplying customers with our own versions of MTF, including a low viscosity MTF (called "MTFGlide," 7.5 cSt (75W80)), and MTL-P (MTL Purple, 11 cSt, 75W85)) customer feedback showed no problems with the Tremec series of transmissions. These fluids had the same AW additives and friction modifiers as did our 75W90 MTF called MTL-R (14.5 cSt, MTL-red).
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