Manual Trans Fluid
Thread Starter
Instructor
Joined: Sep 2007
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Manual Trans Fluid
Has anyone replaced their manual trans fluid with something other than the stock Dexron fluid?
If so, have you notice a significant improvement in cold shifts, like when it is around 30 to 40 degrees outside for the first few shifts?
Mine is very notchy in those temps when cold going into second and third; but when warmed up (within a few minutes) it shifts very smoothly. So I was wondering if something like Redline's MTL would help with the cold shifts.
If so, have you notice a significant improvement in cold shifts, like when it is around 30 to 40 degrees outside for the first few shifts?
Mine is very notchy in those temps when cold going into second and third; but when warmed up (within a few minutes) it shifts very smoothly. So I was wondering if something like Redline's MTL would help with the cold shifts.
Le Mans Master
Joined: Jan 2005
Posts: 5,611
Likes: 5
From: Thousand Oaks California
I am using Mobil 1 synthetic Dexron III Spec H ATF.
The shifts are the same. It never gets cold here.
Redline MTL does not meet the "H" specification for the Tremec T-56.
The shifts are the same. It never gets cold here.
Redline MTL does not meet the "H" specification for the Tremec T-56.
Last edited by calemasters; Dec 1, 2007 at 09:09 AM.
Racer
Joined: May 2007
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From: Townsend MA
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Thread Starter
Instructor
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Le Mans Master
Joined: Jan 2005
Posts: 5,611
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From: Thousand Oaks California
This specification "H" for DEXRON III, H Revision, Automatic Transmission Fluid is primarily for use in General Motors transmissions. Specification "H" describes the requirements for a minimum-performance of the transmission fluid. This would include operating temperatures, frictional characteristics and service life of the lubricant.
If the ATF meets Spec H, it will state this on the label.
If the ATF meets Spec H, it will state this on the label.
CF Senior Member
Joined: Feb 2006
Posts: 23,313
Likes: 25
From: Tucson Arizona
I wasn't having any problems with my transimission but I also went to Royal Purple Syncromax. It wouldn't say there was a significant improvement but there was some improvement (of course, shifting will likely feel better anytime you put-in fresh fluid). I would recommend Royal Purple...it works well for me.
Former Vendor
Joined: Aug 2005
Posts: 16,897
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From: Lewisville TX
St. Jude Donor '03-'04-'05-'06-'07-'08-'09-'10-'11-'12-'13
Do not use MTL in the transmissions, we have used RedLine D4 ATF in the street cars and race cars alike with 0 issues.
Some of the gentlemen at RedLine have told me under severe conditions to mix in less than a quart of MTL to the D4 however to help under extreme temperature conditions.
Some of the gentlemen at RedLine have told me under severe conditions to mix in less than a quart of MTL to the D4 however to help under extreme temperature conditions.
Le Mans Master
Joined: Aug 1999
Posts: 5,411
Likes: 2
From: N Carolina 08 Z51 Coupe
Do not use MTL in the transmissions, we have used RedLine D4 ATF in the street cars and race cars alike with 0 issues.
Some of the gentlemen at RedLine have told me under severe conditions to mix in less than a quart of MTL to the D4 however to help under extreme temperature conditions.
Some of the gentlemen at RedLine have told me under severe conditions to mix in less than a quart of MTL to the D4 however to help under extreme temperature conditions.
Thread Starter
Instructor
Joined: Sep 2007
Posts: 168
Likes: 0
Do not use MTL in the transmissions, we have used RedLine D4 ATF in the street cars and race cars alike with 0 issues.
Some of the gentlemen at RedLine have told me under severe conditions to mix in less than a quart of MTL to the D4 however to help under extreme temperature conditions.
Some of the gentlemen at RedLine have told me under severe conditions to mix in less than a quart of MTL to the D4 however to help under extreme temperature conditions.
Royal Purple said that they recommend staying with the OEM fluid for warranty reasons, but that their Synchromax as it is an alteration of an ATF with the added performance additives and this would be their recommendation for the Corvette manual transmission, if you wanted an improvement. But that it is not GM approved and could void warranty. (the purple color would be a dead giveaway)
No response from Mobil1 yet.
Thread Starter
Instructor
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Have you had your car frozen outside for a while and then driveway when it is stone cold? (below 40 degrees) if so, is the shift to 2nd and 3rd very notchy when cold and the butter smooth when warmed up?
Drifting
Joined: Jun 2005
Posts: 1,837
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I'm using Mobil 1 ATF; maybe a little better than the factory fill but not a big difference. It is marked "H Spec" on the bottle.
Royal Purple Synchromax seems to be the favorite among those that have tried it; but technically it doesn't meet the spec and could cause a warranty issue. I think this has more to do with not being willing to pay the testing costs and licensing fee for a product mix that doesn't have a wide application than thinking that it wouldn't qualify, at least in the areas relevant to a manual box.
So I wonder - has anyone tried Dexron VI? And would there be any point to it? It is supposed to have more consistent viscosity, as well as being a better lubricant.
Royal Purple Synchromax seems to be the favorite among those that have tried it; but technically it doesn't meet the spec and could cause a warranty issue. I think this has more to do with not being willing to pay the testing costs and licensing fee for a product mix that doesn't have a wide application than thinking that it wouldn't qualify, at least in the areas relevant to a manual box.
So I wonder - has anyone tried Dexron VI? And would there be any point to it? It is supposed to have more consistent viscosity, as well as being a better lubricant.
Melting Slicks
Joined: Feb 2006
Posts: 3,271
Likes: 182
From: Manassas VA
I'm using Mobil 1 ATF; maybe a little better than the factory fill but not a big difference. It is marked "H Spec" on the bottle.
Royal Purple Synchromax seems to be the favorite among those that have tried it; but technically it doesn't meet the spec and could cause a warranty issue. I think this has more to do with not being willing to pay the testing costs and licensing fee for a product mix that doesn't have a wide application than thinking that it wouldn't qualify, at least in the areas relevant to a manual box.
So I wonder - has anyone tried Dexron VI? And would there be any point to it? It is supposed to have more consistent viscosity, as well as being a better lubricant.
Royal Purple Synchromax seems to be the favorite among those that have tried it; but technically it doesn't meet the spec and could cause a warranty issue. I think this has more to do with not being willing to pay the testing costs and licensing fee for a product mix that doesn't have a wide application than thinking that it wouldn't qualify, at least in the areas relevant to a manual box.
So I wonder - has anyone tried Dexron VI? And would there be any point to it? It is supposed to have more consistent viscosity, as well as being a better lubricant.
My 06 C6 shifting improved greatly when I installed RP Sychromax. Apparently my 08 Z06 doesn't require any as they either improved the transmission, the fluid or the shifter greatly or all incrementally. This transmission shifts really smoothly even when ice cold.