View Poll Results: Which fluid is best for a M12 T56?
Redline D4 ATF
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53
8.85%
Royal Purple Syncromax
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179
29.88%
GM Syncromesh
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154
25.71%
OEM Dexron III ATF
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213
35.56%
Voters: 599. You may not vote on this poll
Which T56 fluid?
#141
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I don't think I saw a post about this but if you have a 98-00 trans that has not been rebuilt with carbon fiber blocker rings you should not use synthetic. There is a good write up on LS2.com here is the link. I have a 98 I rebuilt my trans because my blocker rings were shot I use synchromesh in it now. hope this helps
#142
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Red_Dragon- The guys over at LS1 (same as LS2).com and I had gone around on this before.
I'd created a thread over at LS1.com that had the same thread title and initial post as the one here, linked below:
Ending the speculation: Blocker rings, who's had them fail?
Unfortunately, the LS1.com forum went down or something, because that thread isn't available anymore....too bad, because there was good debate there on the subject.
What is clear is that there are many folks that have posted here that have been running synthetic in their non-rebuilt 98-00 F-body T-56's and have had, at worst, no change compared to dino Dex III, and at best, good improvent over dino Dex III. The fact that many of them have been running the synthetic for many 1000's of miles, and drive their cars both easy and hard, sometimes is lost on the Synthetic is bad for your T-56 crowd.
I'll freely admit however that other have put the same fluid others have used successfully (in 98-00 F-body T-56's), in their own 98-00 F-body T-56's, and have had bad results.
It seems to be a dice roll on whether or not synthetic fluid will work well or not in T-56's...I'd say most have an experience that ranges from "No change over dino Dex III" to "Yeah, that sh*t kicks 8ss!"...however, some have negative results.
In the end, it's just like any other mod to your car...it should be OK, and you hope it's going to do something positive...but, there's always the chance that something negative will happen.
Chuck
I'd created a thread over at LS1.com that had the same thread title and initial post as the one here, linked below:
Ending the speculation: Blocker rings, who's had them fail?
Unfortunately, the LS1.com forum went down or something, because that thread isn't available anymore....too bad, because there was good debate there on the subject.
What is clear is that there are many folks that have posted here that have been running synthetic in their non-rebuilt 98-00 F-body T-56's and have had, at worst, no change compared to dino Dex III, and at best, good improvent over dino Dex III. The fact that many of them have been running the synthetic for many 1000's of miles, and drive their cars both easy and hard, sometimes is lost on the Synthetic is bad for your T-56 crowd.
I'll freely admit however that other have put the same fluid others have used successfully (in 98-00 F-body T-56's), in their own 98-00 F-body T-56's, and have had bad results.
It seems to be a dice roll on whether or not synthetic fluid will work well or not in T-56's...I'd say most have an experience that ranges from "No change over dino Dex III" to "Yeah, that sh*t kicks 8ss!"...however, some have negative results.
In the end, it's just like any other mod to your car...it should be OK, and you hope it's going to do something positive...but, there's always the chance that something negative will happen.
Chuck
#143
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I rebuilt my T-56.
I used Mobil1 syn. and then swapped to Valvoline dex III (the cheap stuff). The shifts got notchier and the gears started to grind. When the tranny was cold it shifted like total ****. Went back to Mobil 1 syn and everything is normal again. Smooth engagment and doesn't react to the cold.
.02
Might try GM stuff next just to see what difference it makes.
I used Mobil1 syn. and then swapped to Valvoline dex III (the cheap stuff). The shifts got notchier and the gears started to grind. When the tranny was cold it shifted like total ****. Went back to Mobil 1 syn and everything is normal again. Smooth engagment and doesn't react to the cold.
.02
Might try GM stuff next just to see what difference it makes.
#146
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Originally Posted by demonspeed
Always used Synchromesh in Tremecs.
#147
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I think its hard to use peoples experiences because a lot of t56 problems are caused by the drivers ability(or lack thereof). A bad driver tears up his tranny then says such and such fluid is no good. Ive always used the GM dex III in my untouched oo t56 and have had zero problems.
#149
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Originally Posted by black00TA
yeah, for those of us who are still running on pre '01 transmisions...
we are all very much aware for this thank you.
we are all very much aware for this thank you.
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#150
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BIG BAD BLACKSS- The 98-00 F-body T-56's used paper/fiber/whatever you want to call it blockers, instead of the carbon ones used in 01+ F-body T-56's.
For those the make the argument that synthetic and/or non-Dexron III rated fluid is bad for 98-00 T-56's, this is the main reason...hence the thread I linked to in my reply to Red_Dragon.
Chuck
For those the make the argument that synthetic and/or non-Dexron III rated fluid is bad for 98-00 T-56's, this is the main reason...hence the thread I linked to in my reply to Red_Dragon.
Chuck
#151
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For all you wondering about the Specialty Formulations Synchroglide, so far, I've had great luck with it. Cold shifts are much smoother than when I had the dino Dex III in there, and warm shifts are a little better too (although it shifted smooth before under the same conditions). Rowing through the gears is no problem either...no grinding on high RPM shifts at all. I also used to have a fair amount of gear noise from the tranny in 1st gear, and that has been quieted considerably.
Questions? Let me know...
Questions? Let me know...
#155
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Originally Posted by Tobynine9
Don't know if I've given my .02 yet.
Per my transmission rebuilder, who's rebuilt T56s for numerous hi-perf shops in my area, don't use Dex III. Only use Synchromesh or similar (either RP Synchromax or Amsoil Synchromesh). The Dex III is recommended by GM because it will lubricate the tranny internals better than the alternatives when cold, preventing unecessary wear from morons who don't warm it up before beating on it. But the Synchromesh will take care of everything MUCH better when warm, which is where 80%+ of your shifting is done (especially if you care about your car enough to join and post on a forum like this).
Per my transmission rebuilder, who's rebuilt T56s for numerous hi-perf shops in my area, don't use Dex III. Only use Synchromesh or similar (either RP Synchromax or Amsoil Synchromesh). The Dex III is recommended by GM because it will lubricate the tranny internals better than the alternatives when cold, preventing unecessary wear from morons who don't warm it up before beating on it. But the Synchromesh will take care of everything MUCH better when warm, which is where 80%+ of your shifting is done (especially if you care about your car enough to join and post on a forum like this).
Last edited by Domestic Demon; 05-02-2006 at 08:46 PM.
#156
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Originally Posted by bad6as
i have amsoil atf as stated, but im switching to amsoil's syncromesh
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#157
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Been running mobil 1 for almost a month now, I had an issue prior to switchng of 2nd gear grinding at 4k rpm or WOT runs.
I'd like to report that I haven't had a grind since switching. I flushed out the old transmission fluid first with some cheap dexron III and a about a day's worth of driving. Came out looking like a pearl paint.
I'd like to report that I haven't had a grind since switching. I flushed out the old transmission fluid first with some cheap dexron III and a about a day's worth of driving. Came out looking like a pearl paint.