Synthetic transmission fluid
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Jan 5, 2024, 10:47 AM
Le Mans Master
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Like mentioned the early (pre-2000) T-56 used paper blocker rings behind the sychros. Some synthetics could POTENIALLY cause accelerated wear of these blocker rings. Chances are the ones who experienced issues already had an underlying issue to begin with. Synthetic oils do a much better job as keeping parts clean. They get blamed a lot for damage or leaks when in reality the leak was already there but covered up by sludge until the synthetic cleaned it out. Then rumors start that synthetics cause leaks, etc.
By 2003 the material was changed so you will be fine with a synthetic in yours.
Melting Slicks
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From: Des Plaines, Il
Depends on year. I think all the z06 are late enough that you can use synthetic, but the amsoil synthetic is apparently safe to use on all years. It has the right modifiers to protect the organic synchro friction material.
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Safety Car
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Le Mans Master
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St. Jude Donor '09-'10-'11
Like mentioned the early (pre-2000) T-56 used paper blocker rings behind the sychros. Some synthetics could POTENIALLY cause accelerated wear of these blocker rings. Chances are the ones who experienced issues already had an underlying issue to begin with. Synthetic oils do a much better job as keeping parts clean. They get blamed a lot for damage or leaks when in reality the leak was already there but covered up by sludge until the synthetic cleaned it out. Then rumors start that synthetics cause leaks, etc.
By 2003 the material was changed so you will be fine with a synthetic in yours.
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I have a 98' with the "Paper blocker rings" I did hours and hours of research. In the end I went with the current GM/AC Delco Manual gearbox flavor. PN 88861800. Its a mineral based fluid. The Summit search engine does not list the C5 specifically, but does list this for all Tremec trans used in Corvettes C6 and C7 including the ZR1. In the comments section a couple C5 owners reported in using this fluid as well.
https://www.summitracing.com/parts/ADO-10-4033
GM Tech link on the subject:
https://web.archive.org/web/20140617...hlink/2009/05/
"TIP: Any vehicle that previously used DEXRON-III for a manual transmission or transfer case should now use p/n 88861800 (88861801 in Canada) Manual Transmission and Transfer Case Fluid."
Another tip:
"All licenses for DEXRON-III expired at the end of 2006 and will not be renewed. Fluids sold in the market after that date bearing claims such as "suitable for use in DEXRON-III applications" or similar wording should be avoided, because 'DEXRON-III' fluids are no longer checked and policed by GM and therefore may not be the originally tested and approved formulation."
YMMV
https://www.summitracing.com/parts/ADO-10-4033
GM Tech link on the subject:
https://web.archive.org/web/20140617...hlink/2009/05/
"TIP: Any vehicle that previously used DEXRON-III for a manual transmission or transfer case should now use p/n 88861800 (88861801 in Canada) Manual Transmission and Transfer Case Fluid."
Another tip:
"All licenses for DEXRON-III expired at the end of 2006 and will not be renewed. Fluids sold in the market after that date bearing claims such as "suitable for use in DEXRON-III applications" or similar wording should be avoided, because 'DEXRON-III' fluids are no longer checked and policed by GM and therefore may not be the originally tested and approved formulation."
YMMV
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Safety Car
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From: Canada
I have a 98' with the "Paper blocker rings" I did hours and hours of research. In the end I went with the current GM/AC Delco Manual gearbox flavor. PN 88861800. Its a mineral based fluid. The Summit search engine does not list the C5 specifically, but does list this for all Tremec trans used in Corvettes C6 and C7 including the ZR1. In the comments section a couple C5 owners reported in using this fluid as well.
https://www.summitracing.com/parts/ADO-10-4033
GM Tech link on the subject:
https://web.archive.org/web/20140617...hlink/2009/05/
"TIP: Any vehicle that previously used DEXRON-III for a manual transmission or transfer case should now use p/n 88861800 (88861801 in Canada) Manual Transmission and Transfer Case Fluid."
Another tip:
"All licenses for DEXRON-III expired at the end of 2006 and will not be renewed. Fluids sold in the market after that date bearing claims such as "suitable for use in DEXRON-III applications" or similar wording should be avoided, because 'DEXRON-III' fluids are no longer checked and policed by GM and therefore may not be the originally tested and approved formulation."
YMMV
https://www.summitracing.com/parts/ADO-10-4033
GM Tech link on the subject:
https://web.archive.org/web/20140617...hlink/2009/05/
"TIP: Any vehicle that previously used DEXRON-III for a manual transmission or transfer case should now use p/n 88861800 (88861801 in Canada) Manual Transmission and Transfer Case Fluid."
Another tip:
"All licenses for DEXRON-III expired at the end of 2006 and will not be renewed. Fluids sold in the market after that date bearing claims such as "suitable for use in DEXRON-III applications" or similar wording should be avoided, because 'DEXRON-III' fluids are no longer checked and policed by GM and therefore may not be the originally tested and approved formulation."
YMMV
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From: SW CO
I have a 98' with the "Paper blocker rings" I did hours and hours of research. In the end I went with the current GM/AC Delco Manual gearbox flavor. PN 88861800. Its a mineral based fluid. The Summit search engine does not list the C5 specifically, but does list this for all Tremec trans used in Corvettes C6 and C7 including the ZR1. In the comments section a couple C5 owners reported in using this fluid as well.
https://www.summitracing.com/parts/ADO-10-4033
GM Tech link on the subject:
https://web.archive.org/web/20140617...hlink/2009/05/
"TIP: Any vehicle that previously used DEXRON-III for a manual transmission or transfer case should now use p/n 88861800 (88861801 in Canada) Manual Transmission and Transfer Case Fluid."
Another tip:
"All licenses for DEXRON-III expired at the end of 2006 and will not be renewed. Fluids sold in the market after that date bearing claims such as "suitable for use in DEXRON-III applications" or similar wording should be avoided, because 'DEXRON-III' fluids are no longer checked and policed by GM and therefore may not be the originally tested and approved formulation."
YMMV
https://www.summitracing.com/parts/ADO-10-4033
GM Tech link on the subject:
https://web.archive.org/web/20140617...hlink/2009/05/
"TIP: Any vehicle that previously used DEXRON-III for a manual transmission or transfer case should now use p/n 88861800 (88861801 in Canada) Manual Transmission and Transfer Case Fluid."
Another tip:
"All licenses for DEXRON-III expired at the end of 2006 and will not be renewed. Fluids sold in the market after that date bearing claims such as "suitable for use in DEXRON-III applications" or similar wording should be avoided, because 'DEXRON-III' fluids are no longer checked and policed by GM and therefore may not be the originally tested and approved formulation."
YMMV
As part of your investigation, did you consider Redline D4 ATF? It is what Redline recommends for our cars.
Melting Slicks
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I used Amsoil synthetic on my '03 T56, no issues.
Burning Brakes
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https://www.corvetteforum.com/forums...fo-thread.html
Here is a snip:
