80W90 GL4 Only!!
Had a 1976 L-82, 4-sp
Joined: Mar 2011
Posts: 5,338
Likes: 1,213
From: Some days your the dog and some days your the hydrant.
Royal Canadian Navy
Or GL-5 dino which is the recommended oil back in the day. Open my link and read what Redline has to say about their oil.
Le Mans Master
Joined: Oct 2007
Posts: 9,698
Likes: 3,468
From: Akron Ohio
2025 Corvette of the Year Finalist - Modified
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St. Jude Donor '09-'10-'11
Interesting that no one has mentioned what GM recommends.
That would be GM Synchromesh Fluid. I used that in my Muncie for years, and since Tremec recommends it for their TKO transmissions, I use it in my TKO600.
Also it gets high praises from the import crowd.
More info.........
http://www.bobistheoilguy.com/forums...Number=1114224
That would be GM Synchromesh Fluid. I used that in my Muncie for years, and since Tremec recommends it for their TKO transmissions, I use it in my TKO600.
Also it gets high praises from the import crowd.
More info.........
http://www.bobistheoilguy.com/forums...Number=1114224
I use the AMSOIL GL4 Manual Transmission and Transaxle lube in my Muncie.
http://www.amsoil.com/shop/by-produc...-EA?zo=1934716
Thread Starter
Pro
Joined: Dec 2011
Posts: 626
Likes: 15
From: Austin, TX
Le Mans Master
Joined: Dec 2003
Posts: 5,727
Likes: 38
From: Fremont CA
Interesting that no one has mentioned what GM recommends.
That would be GM Synchromesh Fluid. I used that in my Muncie for years, and since Tremec recommends it for their TKO transmissions, I use it in my TKO600.
Also it gets high praises from the import crowd.
More info.........
http://www.bobistheoilguy.com/forums...Number=1114224
That would be GM Synchromesh Fluid. I used that in my Muncie for years, and since Tremec recommends it for their TKO transmissions, I use it in my TKO600.
Also it gets high praises from the import crowd.
More info.........
http://www.bobistheoilguy.com/forums...Number=1114224
For a Muncie 4 speed, you need a 80/90W gear oil rated "MT-1" for a transmission with bronze Syncro blocker rings. I like the Brad Penn gear lube, Amsoil has a synthetic rated MT-1, SWEPCO 201, Torco....which is what Richmond uses in their T-10 style transmissions.
I don't really care much for Sta-Lube products or many of the brands found at your FLAPS.
Link: http://www.summitracing.com/parts/bp...MobileSwitchNo
Instructor
Joined: Nov 2014
Posts: 129
Likes: 56
From: Tequesta FL
The GL5 oils do not damage the rings. Its a great marketing stunt that has created a demand for older GL-4 grade oils. Brad Penn makes a classic GL-4 now Driven oils has come up with a part synthetic GL-4.
GL-5 oils have more Sulfur content than GL-4. The "corrosion" you hear about will only happen if the GL-5 goes over 300 degrees. The "corrosion" will actually amount to a discoloration of the bronze ring to a dark brown color.
I've built 1000's of gearboxes never seen an issue with both GL-5 or GL4 oils. However people are demanding GL-4 oils now because of the hype generated on the internet. Typically I'm selling the Brad Penn Classic GL-4, The new Driven GL-4 as well as Royal Purple Max Gear lube 75wt. The Royal Purple is in all our endurance race boxes.
Paul
GL-5 oils have more Sulfur content than GL-4. The "corrosion" you hear about will only happen if the GL-5 goes over 300 degrees. The "corrosion" will actually amount to a discoloration of the bronze ring to a dark brown color.
I've built 1000's of gearboxes never seen an issue with both GL-5 or GL4 oils. However people are demanding GL-4 oils now because of the hype generated on the internet. Typically I'm selling the Brad Penn Classic GL-4, The new Driven GL-4 as well as Royal Purple Max Gear lube 75wt. The Royal Purple is in all our endurance race boxes.
Paul
Had a 1976 L-82, 4-sp
Joined: Mar 2011
Posts: 5,338
Likes: 1,213
From: Some days your the dog and some days your the hydrant.
Royal Canadian Navy
The GL5 oils do not damage the rings. Its a great marketing stunt that has created a demand for older GL-4 grade oils. Brad Penn makes a classic GL-4 now Driven oils has come up with a part synthetic GL-4.
GL-5 oils have more Sulfur content than GL-4. The "corrosion" you hear about will only happen if the GL-5 goes over 300 degrees. The "corrosion" will actually amount to a discoloration of the bronze ring to a dark brown color.
I've built 1000's of gearboxes never seen an issue with both GL-5 or GL4 oils. However people are demanding GL-4 oils now because of the hype generated on the internet. Typically I'm selling the Brad Penn Classic GL-4, The new Driven GL-4 as well as Royal Purple Max Gear lube 75wt. The Royal Purple is in all our endurance race boxes.
Paul
GL-5 oils have more Sulfur content than GL-4. The "corrosion" you hear about will only happen if the GL-5 goes over 300 degrees. The "corrosion" will actually amount to a discoloration of the bronze ring to a dark brown color.
I've built 1000's of gearboxes never seen an issue with both GL-5 or GL4 oils. However people are demanding GL-4 oils now because of the hype generated on the internet. Typically I'm selling the Brad Penn Classic GL-4, The new Driven GL-4 as well as Royal Purple Max Gear lube 75wt. The Royal Purple is in all our endurance race boxes.
Paul
Instructor
Joined: Nov 2014
Posts: 129
Likes: 56
From: Tequesta FL
I don't like to think of it as an internet myth but prior to forums and discussion boards people used whatever was in the auto parts store. You purchased gear lube at whatever viscosity you needed and that was it. Now instead if walking into the store and buying a couple of quarts of oil the consumer feels smart about researching online and asking questions and getting answers from people who for the most part rehash more information they have read about on forums and have very little to do with transmission repair ending up with threads like this. If you are in the oil business logic has it that if you get a leg up on the competition by offering something nobody else has then its a sale made and your brand may be used for diffs and engines as well. I sold and used Valvoline for years as well as Pennzoil. Never had an issue . Now Im stocking the Brad Penn and Driven GL4 oils which are relatively new to the market because of the frenzy created from online communities and to be honest because these oils are not in stores I sell more oil than I ever did.
Last edited by 4speeds; May 19, 2016 at 01:43 AM.
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Instructor
Joined: Nov 2014
Posts: 129
Likes: 56
From: Tequesta FL
Paul
Last edited by 4speeds; May 19, 2016 at 01:49 AM.