What tranny fluid for a T56?
#21
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For you RP users
From six speeds, inc.
: What transmission fluid do you recommend?
A: We use Mobil 1 ATF in all of our daily drivers. While Mobil 1 is what is desired some customers have trouble finding it in there locations. We also use GM Synchromesh. Royal Purple should not be used in a stock transmission as it has been known to cause premature blocker ring wear.
I was using RP for awhile but recently changed back to regular atf rp synchromesh was way smoother, I think now I'm going to try gm/pennzoil sycromesh. Regular atf is way notcher hopefully the gm/pennzoil sycromesh will take car of some of it.
From six speeds, inc.
: What transmission fluid do you recommend?
A: We use Mobil 1 ATF in all of our daily drivers. While Mobil 1 is what is desired some customers have trouble finding it in there locations. We also use GM Synchromesh. Royal Purple should not be used in a stock transmission as it has been known to cause premature blocker ring wear.
I was using RP for awhile but recently changed back to regular atf rp synchromesh was way smoother, I think now I'm going to try gm/pennzoil sycromesh. Regular atf is way notcher hopefully the gm/pennzoil sycromesh will take car of some of it.
Last edited by JonB; 08-31-2007 at 06:41 PM.
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Originally Posted by JonB
While Mobil 1 is what is desired some customers have trouble finding it in there locations.
Still a helluva lot easier to find than the GM/Pennzoil Synchromesh, and waaaay easier to find than GC motor oil!!!
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Countless posts and two friends...but no experience of your own.
Instead of spreading internet folklore, do me a favor and try some yourself and see what you think. Only then will I count your post as an opinion worth anything. This is how internet rumors propagate.
I've used synthetic transmission oil for at least a year, and it shifts smoother with it than without. But that's MY experience (not my friend's, and not somebody's brother that posts over on another forum).
As long as it is Dexron III compatible, it should be fine.
Instead of spreading internet folklore, do me a favor and try some yourself and see what you think. Only then will I count your post as an opinion worth anything. This is how internet rumors propagate.
I've used synthetic transmission oil for at least a year, and it shifts smoother with it than without. But that's MY experience (not my friend's, and not somebody's brother that posts over on another forum).
As long as it is Dexron III compatible, it should be fine.
I've been having some issues with my synchros, i think ill try some synchromesh.
#27
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Let us know how yours does at high RPMs when you feel like really giving your new clutch a real workout with some 6000 RPM shifts through multiple gears. I'm curious to see if you have issues or not.
That said, I have recently read bad things about Royal Purple from Six Speeds Inc regarding blocker rings, which would eventually cause trouble shifting if it damages the blocker rings. I think I'm going to start using the Mobil 1 ATF like they do.
Last edited by PewterScreaminMach; 02-04-2008 at 01:37 PM.
#28
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I don't think this is valid, Aaron. Ron currently uses Royal Purple and his car is the smoothest shifting car I've ever driven (and have you ever seen him shift? NO hesitation whatsoever). And my shifting issue at high RPMs most likely has to do with a clutch disengagement problem, not a transmission fluid problem. At low RPMs, it shifts fine.
Let us know how yours does at high RPMs when you feel like really giving your new clutch a real workout with some 6000 RPM shifts through multiple gears. I'm curious to see if you have issues or not.
That said, I have recently read bad things about Royal Purple from Six Speeds Inc regarding blocker rings, which would eventually cause trouble shifting if it damages the blocker rings. I think I'm going to start using the Mobil 1 ATF like they do.
Let us know how yours does at high RPMs when you feel like really giving your new clutch a real workout with some 6000 RPM shifts through multiple gears. I'm curious to see if you have issues or not.
That said, I have recently read bad things about Royal Purple from Six Speeds Inc regarding blocker rings, which would eventually cause trouble shifting if it damages the blocker rings. I think I'm going to start using the Mobil 1 ATF like they do.
As state Six Speeds dont recommend it (royal purple), countless post of people having issues with fluids and I just posted saying that I learned alot and ive gone to regular non syn fluid and works fine.
BTW, I took her out this morning, 3 dead stop WOT 1-2, 2-3, 3-4 and even 4-5 @ 4:45 this morning on Rt 691 and no issues. No grinding, very positive clean shifts. NO dead pedal
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Here we go again.
I have used only Dextron fluid in 2 different F-bodies for 13 years. This recommendation is printed on a lable on the bottom of the factory GM tranny.
Apparently, the stock sycro/blocker rings in a T56 are coated with a non-metalic material that can deteriorate if exposed to some of the additives contained in certain synthetic lubricants. So, some synthetics are OK, others are not.
To be safe, you can't go wrong with Dextron. I think "Dextron 3" is no longer sold but a newer version of Dextron is widely availible for use in our gear boxes.
I have used only Dextron fluid in 2 different F-bodies for 13 years. This recommendation is printed on a lable on the bottom of the factory GM tranny.
Apparently, the stock sycro/blocker rings in a T56 are coated with a non-metalic material that can deteriorate if exposed to some of the additives contained in certain synthetic lubricants. So, some synthetics are OK, others are not.
To be safe, you can't go wrong with Dextron. I think "Dextron 3" is no longer sold but a newer version of Dextron is widely availible for use in our gear boxes.
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im running non synthetic dex III in my tranny! the owner b4 me claims he was using M1 fluid only in the car and including the tranny, after i switched to non syn chevron dex III i felt a smother shift!! it could also have been that the old fluid was dirty, dident look to dirty tho, now since i have a third gear grind at high rpm, im thinking about switching to syncromesh!
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Ive been using royal purple for a couple years now and have had no problems like some people are having. I was also told that the blocker ring problem was on 2000 and down t56's and that the 01 and up was ok to use. but, I could be mis informed.
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I replaced my fluid at 78,000 miles with Amsoil Synthetic Synchromesh. 2000 model T-56.
Honestly could not tell a bit of difference other than shifting when it
was really cold outside (25 or so degrees). Is just a hair smoother when cold.
Didnt know about the blocker ring problem, hmm may change it back, dammit that **** is expensive!
Honestly could not tell a bit of difference other than shifting when it
was really cold outside (25 or so degrees). Is just a hair smoother when cold.
Didnt know about the blocker ring problem, hmm may change it back, dammit that **** is expensive!
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I USED RP SYN WITH C/F SYNCHRO BUILD UP AND IT RUINED MY CARBON FIBER SYNCHROS.CHECK WITH AMBER AT T-56 REBUILDS OR D&D PERF.USE DEX 3 OR MOBILE 1 ONLY.NOW I AM LOOKING AT A $700.00 FIX .'72SS CAMARO LS1 6SP,MS3,TSP 5.3'S,4:11'S,11.58 AT 119MPH,1.65 60'![Driving](https://ls1tech.com/forums/images/smilies/LS1Tech/gr_driving3.gif)
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