1994 M6 corvette
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Team Owner
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At 128K I might be more concerned with a couple other things, 1.) How removeable are the drain and fill plugs & 2.) should I consider a change and a short 1 or 2K mile for a flush of sorts. If you did or thought you'd like to do the drive/flush maybe the suggested in post #3 is maybe for the 'final' and not the first. Choice might also depend upon your relationship with various vendors if $$$ matter,
If you know or suspect yours will be it's 1st I believe you buy 2 replacement plugs before anything and consider a 1 or 2K mile drive and then maybe repeat. If you knew it had been serviced previously maybe when, at what miles might and brand used might be good to know.
A VW drain plug will work for replacements. VW part # WHT-001-937 but you need to be sure you ask for M17 Hex, they likely offer still a 'spline' drive used much later. Plugs should be available 'locally'.
If you know or suspect yours will be it's 1st I believe you buy 2 replacement plugs before anything and consider a 1 or 2K mile drive and then maybe repeat. If you knew it had been serviced previously maybe when, at what miles might and brand used might be good to know.
A VW drain plug will work for replacements. VW part # WHT-001-937 but you need to be sure you ask for M17 Hex, they likely offer still a 'spline' drive used much later. Plugs should be available 'locally'.
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What's with the chill?
5W-30 GM 1052931 was the original service fluid and NOT until several years after end of production, when GM introduced the product you mentioned it was never approved for service until many years later.
If you use the GM 1052931 and conversions you'll find several products. Royal Purple comes to mind as suggested HPS or XPR 5W-30. Maybe later than 2005 or so GM actually began to acknowledge their 12345349 would be acceptable. That product now would likely be 88900333. Many use the product you use. BUT it was NEVER ORIGINAL> NEVER! I still have some 1052931.
5W-30 GM 1052931 was the original service fluid and NOT until several years after end of production, when GM introduced the product you mentioned it was never approved for service until many years later.
If you use the GM 1052931 and conversions you'll find several products. Royal Purple comes to mind as suggested HPS or XPR 5W-30. Maybe later than 2005 or so GM actually began to acknowledge their 12345349 would be acceptable. That product now would likely be 88900333. Many use the product you use. BUT it was NEVER ORIGINAL> NEVER! I still have some 1052931.
Drifting
Joined: Aug 2002
Posts: 1,775
Likes: 125
From: Birmingham AL
Okay. Thank you for the information. Did not realize that GM synchromesh was not original. Will consult my FSM before making false statements about world ending transmission fluid decisions.
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Intermediate
Joined: Jul 2024
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Thread Starter
Intermediate
Joined: Jul 2024
Posts: 30
Likes: 2
What's with the chill?
5W-30 GM 1052931 was the original service fluid and NOT until several years after end of production, when GM introduced the product you mentioned it was never approved for service until many years later.
If you use the GM 1052931 and conversions you'll find several products. Royal Purple comes to mind as suggested HPS or XPR 5W-30. Maybe later than 2005 or so GM actually began to acknowledge their 12345349 would be acceptable. That product now would likely be 88900333. Many use the product you use. BUT it was NEVER ORIGINAL> NEVER! I still have some 1052931.
5W-30 GM 1052931 was the original service fluid and NOT until several years after end of production, when GM introduced the product you mentioned it was never approved for service until many years later.
If you use the GM 1052931 and conversions you'll find several products. Royal Purple comes to mind as suggested HPS or XPR 5W-30. Maybe later than 2005 or so GM actually began to acknowledge their 12345349 would be acceptable. That product now would likely be 88900333. Many use the product you use. BUT it was NEVER ORIGINAL> NEVER! I still have some 1052931.
Last edited by Ayjoki; Jul 11, 2024 at 09:39 AM.
Team Owner
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If you have a relationship with NAPA you might consider maybe Royal Purple Synchromax that replaces the GM #12345349. There's many quality products available. Do your own research.
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I have, seems that Royal Purple Synchromax is too thin compared to amsoil and gm. Has any here used vavoline synchromesh?
Racer
Joined: May 2007
Posts: 306
Likes: 49
From: Florida
I see there is a product a reputable Corvette aftermarket company sells that is called BG Snycroshift and is 75W-80. The original oil was 5W-30. The only product I can find locally is Valvoline Syncromesh but the bottle does not say the weight. Does anyone know the weight of the Amsoil or the GM Syncromesh?