Royal Purple Synchromax
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Joined: Nov 2005
Posts: 57
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From: St. Louis Missouri
Royal Purple Synchromax
Thought I might get more responses on this forum. I originally started this on the general forum and so far I am being told that the Synchromax does not meet the Spec "H" standard. From other threads it appears that many of you have already made this switch. Any concerns that it does not meet the specs? Has anyone actually contacted Royal Purple? Any knowledge on exactly what Spec "H" means and comparison data between the two? My guess is that the Synchromax exceeds the standard by it that were the case you would think they would advertise it. Any discussions with your servicing dealers on whether using Synchromax could impact the warranty? Are there other options that will help smooth out the shifting that does meet specs? Lots of questions. Any help will be most appreciated.
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Advanced
Joined: Nov 2005
Posts: 57
Likes: 0
From: St. Louis Missouri
For those interested, here is the response I received from Royal Purple:
The GM warranty approved product is a automatic transmission fluid meeting GM Dexron IIIH specs. This would be the RP MaxATF. A fully synthetic atf meeting the GM Dexron IIIH specs and will maintain your warranty. A fluid such as the RP Synchromax which contains additional additive technology for improved wear protection but different than an Dexron atf can not be a warranty approved product. You can't get increased performance and meet warranty due to the restrictions placed by GM.
So if what you are looking for is maintaining warranty with an 'equivalent' product to the factory fill we recommend the RP MaxATF.
If you are looking for improved shift performance as well as increased wear protection on the bearings and gears in your manual transmission, rather than using an atf designed for automatics - we recommend our RP Synchromax Manual Transmission Fluid made specifically to improve the performance of manual transmissions using atf as a fluid from the factory.
The GM warranty approved product is a automatic transmission fluid meeting GM Dexron IIIH specs. This would be the RP MaxATF. A fully synthetic atf meeting the GM Dexron IIIH specs and will maintain your warranty. A fluid such as the RP Synchromax which contains additional additive technology for improved wear protection but different than an Dexron atf can not be a warranty approved product. You can't get increased performance and meet warranty due to the restrictions placed by GM.
So if what you are looking for is maintaining warranty with an 'equivalent' product to the factory fill we recommend the RP MaxATF.
If you are looking for improved shift performance as well as increased wear protection on the bearings and gears in your manual transmission, rather than using an atf designed for automatics - we recommend our RP Synchromax Manual Transmission Fluid made specifically to improve the performance of manual transmissions using atf as a fluid from the factory.
Burning Brakes
Joined: Aug 2000
Posts: 887
Likes: 10
From: Ontario New York
Originally Posted by GaryNL
For those interested, here is the response I received from Royal Purple:
The GM warranty approved product is a automatic transmission fluid meeting GM Dexron IIIH specs. This would be the RP MaxATF. A fully synthetic atf meeting the GM Dexron IIIH specs and will maintain your warranty. A fluid such as the RP Synchromax which contains additional additive technology for improved wear protection but different than an Dexron atf can not be a warranty approved product. You can't get increased performance and meet warranty due to the restrictions placed by GM.
So if what you are looking for is maintaining warranty with an 'equivalent' product to the factory fill we recommend the RP MaxATF.
If you are looking for improved shift performance as well as increased wear protection on the bearings and gears in your manual transmission, rather than using an atf designed for automatics - we recommend our RP Synchromax Manual Transmission Fluid made specifically to improve the performance of manual transmissions using atf as a fluid from the factory.
The GM warranty approved product is a automatic transmission fluid meeting GM Dexron IIIH specs. This would be the RP MaxATF. A fully synthetic atf meeting the GM Dexron IIIH specs and will maintain your warranty. A fluid such as the RP Synchromax which contains additional additive technology for improved wear protection but different than an Dexron atf can not be a warranty approved product. You can't get increased performance and meet warranty due to the restrictions placed by GM.
So if what you are looking for is maintaining warranty with an 'equivalent' product to the factory fill we recommend the RP MaxATF.
If you are looking for improved shift performance as well as increased wear protection on the bearings and gears in your manual transmission, rather than using an atf designed for automatics - we recommend our RP Synchromax Manual Transmission Fluid made specifically to improve the performance of manual transmissions using atf as a fluid from the factory.
Safety Car
Joined: Jan 2006
Posts: 4,598
Likes: 78
From: Miami FL
2020 C6 of the Year Finalist - Unmodified
St. Jude Donor '08-'09-'10-'11-'12-'13-'14-'15-'16,'17,'18-'19-'20-'21-'22
I replaced the lubricant in my C6 at about 1200 miles, with 3 quarts of RP Synchromax and 1 quart of Mobil 1 synthetic ATF. The red dye in the Mobil makes the whole charge look like ATF. The light purple color of the synchromax is entirely overwhelmed by the red dye in the Mobil 1.
Oh yeah, the tranny shifts much more smoothly, too.
.
Oh yeah, the tranny shifts much more smoothly, too.
.
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Melting Slicks
Joined: Feb 2006
Posts: 3,271
Likes: 182
From: Manassas VA
All this worrying about the warranty is not justified. If you need the transmission fixed under warranty just change back to the approved fluid before going to the dealer. The Synchromax does produce much smoother shifting than the recommended fluid.
Burning Brakes
Joined: Aug 2000
Posts: 887
Likes: 10
From: Ontario New York
Originally Posted by ronsc1985
All this worrying about the warranty is not justified. If you need the transmission fixed under warranty just change back to the approved fluid before going to the dealer. The Synchromax does produce much smoother shifting than the recommended fluid.
Melting Slicks
Joined: Feb 2006
Posts: 2,007
Likes: 1
From: Eastern PA:ECS Paxton Novi 1500(676rwhp,585tq on stock engine),LG headers, 410's, Corsa Sports, ECS Alky Kit
St. Jude Donor '08-'09
I've got RP Oil, Trans, and Diff fluids in my car. Could feel a difference with shifting when I put it in the trans, smoothed things up a bit.
