What fluids do you recommend for this?
Thread Starter
Burning Brakes
Joined: Oct 2006
Posts: 1,146
Likes: 10
From: Boise Idaho
St. Jude Donor '07
What fluids do you recommend for this?
I'm changing the fluid in my M6 transmission and diff. What fluids do you guys recommend? Redline, royal purple, mobil 1, or just anything synthetic? Thanks.
Tech Contributor
Joined: Dec 1999
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From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
I used Mobile 1 Synthetic ATF. It worked so good in my 98 that I changed out the Tranny fluid in my new (at the time) 17,000 mile ZO6.
The shift quality improved quite a bit in the Z and the rough shift from 2nd to 3rd in the 98 was eliminated. (Yea, yea, I know the 98 has paper lined blocker rings but, the shift quality was noticibly improved and its still good! )
The cost of the Mobile 1 is reasonable and it works extremely well!
BC
The shift quality improved quite a bit in the Z and the rough shift from 2nd to 3rd in the 98 was eliminated. (Yea, yea, I know the 98 has paper lined blocker rings but, the shift quality was noticibly improved and its still good! ) The cost of the Mobile 1 is reasonable and it works extremely well!
BC
Racer
Joined: Jan 2006
Posts: 479
Likes: 2
From: Hollywood Maryland
Be careful about Synthetic ATFs in '99 MN6s
When I did my first MN6 fluid change, I bought MOBIL1 Sysnthetic ATF. Then I began reading here about the use of paper blockers? in earlier C5 MN6s and that most syntherics will damage these. The exception being AMSOil Synthetic ATF. Newer MN6s replaced the paper blockers with composite ones that were tolerant of all fluids. I returned the Mobil1 and put in the AMSOil. Transmission shifts beautifully. I'd recommend the AMSoil. Just my HO.
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Pro
Joined: Sep 2005
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From: Geneva, IL Bring back the Chief!
St. Jude Donor '06-'07-'08-'09-'10,'13-'14,'19-'20-'21-'22
When I did my first MN6 fluid change, I bought MOBIL1 Sysnthetic ATF. Then I began reading here about the use of paper blockers? in earlier C5 MN6s and that most syntherics will damage these. The exception being AMSOil Synthetic ATF. Newer MN6s replaced the paper blockers with composite ones that were tolerant of all fluids. I returned the Mobil1 and put in the AMSOil. Transmission shifts beautifully. I'd recommend the AMSoil. Just my HO.
Racer
Joined: Jan 2006
Posts: 479
Likes: 2
From: Hollywood Maryland
2000 and newer T56s
Doing a search on the Forum, here's what's been posted:
1)1997 through 1999 T56 MN6s in C5 Corvettes used the organic paper (celulos?) blockers in the transmissions.
2) The newer synthetics cause these to swell and eventually fail. AMSOil Synthetic ATF is the exception. (There's an AMSOil vendor on this Forum whom I communicated with on this issue who also confirmed the above)
3)The Tremac T56 design was changed for the 2000 model year where the celulos blocker material was changed to some kind of composite that wasn't prone to swelling, thus reducing the risk of using other synthetics.
Any experts, please step in and correct the information if needed. I'm an owner, not an expert.
As I said, this information was gathered from various posts on the CF. I chose to follow that advice. I used AMSOil Synthetic ATF and have no complaints and no issues in my '99 FRC. T56 shifts smooth and fluid after 8,000 miles.
There's a great CF, vendor - RPM Transmissions, who'll probably give you the straight poop on this topic. If anyone knows they do. Email them.
1)1997 through 1999 T56 MN6s in C5 Corvettes used the organic paper (celulos?) blockers in the transmissions.
2) The newer synthetics cause these to swell and eventually fail. AMSOil Synthetic ATF is the exception. (There's an AMSOil vendor on this Forum whom I communicated with on this issue who also confirmed the above)
3)The Tremac T56 design was changed for the 2000 model year where the celulos blocker material was changed to some kind of composite that wasn't prone to swelling, thus reducing the risk of using other synthetics.
Any experts, please step in and correct the information if needed. I'm an owner, not an expert.
As I said, this information was gathered from various posts on the CF. I chose to follow that advice. I used AMSOil Synthetic ATF and have no complaints and no issues in my '99 FRC. T56 shifts smooth and fluid after 8,000 miles.
There's a great CF, vendor - RPM Transmissions, who'll probably give you the straight poop on this topic. If anyone knows they do. Email them.
Team Owner
Joined: May 2001
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From: Dear Karma, I have a list of people you missed.
St. Jude Donor '08-'09-'10-'11-'12-'13-'14-'15-'16
Doing a search on the Forum, here's what's been posted:
1)1997 through 1999 T56 MN6s in C5 Corvettes used the organic paper (celulos?) blockers in the transmissions.
2) The newer synthetics cause these to swell and eventually fail. AMSOil Synthetic ATF is the exception. (There's an AMSOil vendor on this Forum whom I communicated with on this issue who also confirmed the above)
3)The Tremac T56 design was changed for the 2000 model year where the celulos blocker material was changed to some kind of composite that wasn't prone to swelling, thus reducing the risk of using other synthetics.
Any experts, please step in and correct the information if needed. I'm an owner, not an expert.
As I said, this information was gathered from various posts on the CF. I chose to follow that advice. I used AMSOil Synthetic ATF and have no complaints and no issues in my '99 FRC. T56 shifts smooth and fluid after 8,000 miles.
There's a great CF, vendor - RPM Transmissions, who'll probably give you the straight poop on this topic. If anyone knows they do. Email them.
1)1997 through 1999 T56 MN6s in C5 Corvettes used the organic paper (celulos?) blockers in the transmissions.
2) The newer synthetics cause these to swell and eventually fail. AMSOil Synthetic ATF is the exception. (There's an AMSOil vendor on this Forum whom I communicated with on this issue who also confirmed the above)
3)The Tremac T56 design was changed for the 2000 model year where the celulos blocker material was changed to some kind of composite that wasn't prone to swelling, thus reducing the risk of using other synthetics.
Any experts, please step in and correct the information if needed. I'm an owner, not an expert.
As I said, this information was gathered from various posts on the CF. I chose to follow that advice. I used AMSOil Synthetic ATF and have no complaints and no issues in my '99 FRC. T56 shifts smooth and fluid after 8,000 miles.
There's a great CF, vendor - RPM Transmissions, who'll probably give you the straight poop on this topic. If anyone knows they do. Email them.
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Joined: Aug 2001
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From: King George VA
Thanks for the mention. I agree with the info posted above. I've got numerous customers with 97-99 C5s using the AMSOIL ATF and not one has reported any problems to me.
I use and recommend these:
Tranny: AMSOIL ATF (takes 3.7 quarts)
Diff: AMSOIL Severe Gear Extreme Pressure Synthetic 75w90 (takes 1.7 quarts)
Something like this comes in handy for the do it yourselfer: AMSOIL Hand Pump
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4th Gear
Joined: Mar 2007
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Melting Slicks
Joined: Mar 2000
Posts: 2,975
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From: Northwest Iowa
Thanks for the mention. I agree with the info posted above. I've got numerous customers with 97-99 C5s using the AMSOIL ATF and not one has reported any problems to me.
I use and recommend these:
Tranny: AMSOIL ATF (takes 3.7 quarts)
Diff: AMSOIL Severe Gear Extreme Pressure Synthetic 75w90 (takes 1.7 quarts)
Something like this comes in handy for the do it yourselfer: AMSOIL Hand Pump
I use and recommend these:
Tranny: AMSOIL ATF (takes 3.7 quarts)
Diff: AMSOIL Severe Gear Extreme Pressure Synthetic 75w90 (takes 1.7 quarts)
Something like this comes in handy for the do it yourselfer: AMSOIL Hand Pump
Sub, Do you need to add a positraction additive in the C5 diff. with the AMSOIL?