I have a 2014 3LT Z51 and want to change the manual transmission oil and rear differential oil. Has anyone out there had this done to their car , what type of oil did you use. Just curious what everyone used... thx
M7 Transmission Oil
- Thread starter Pocono kid
- Start date
Found this….
For a 2014 3LT Z51 Corvette:
Transmission Fluid:
• If your Corvette has the 7-speed manual transmission (TR6070), use a synthetic manual transmission fluid such as AMSOIL GLS 75W-90 or a similar high-quality synthetic gear oil. The capacity is around 7.4 to 8.5 pints depending on specific RPO codes.
• For automatic transmissions (6L80 or 8L90), Dexron III or Dexron VI automatic transmission fluid is recommended, with initial fill around 6.7 quarts for 6L80 and 7.4 quarts for 8L90.
Rear Differential Fluid:
• Use a synthetic 75W-90 gear oil with limited slip additive (friction modifier) suitable for electronic limited slip differentials (ELSD). GM part number 10-4034 is commonly used and is a 100% synthetic 75W-90 gear oil designed for Corvette differentials.
• The capacity varies by ratio and whether you have the Z51 package ELSD:
• With Z51 ELSD (2.73 or 3.42 ratio), about 5.7 to 5.8 pints.
• Without Z51, standard differential requires about 5.1 pints.
2019 Stingray, non-Z51. I changed up the M7 transmission fluid @ about 20,000 KM along with the diff oil.
For the tranny (which specifies automatic transmission fluid), the replacement that went in to mine was Royal Purple synchromax, which was purported to make the shifting less notchy especially when cold at first start up before driving. It does make the shifting quite a bit smoother when cold, and like butter after it warms up. I'd use it again in a heartbeat. Here's a link General PDP Template (https://www.canadiantire.ca/en/pdp/royal-purple-synchromax-manual-transmission-fluid-946-ml-0289088p.html?rq=Royal+Purple).
For the diff, with you having a Z51, you have a choice of fluids, either synthetic or Dino oil. Make sure that you have an oil or fluid which has a "friction modifier" or that you have such an add-in modifier to add to the differential. The GM dinosaur transmission fluid specified in your owners manual already incorporates this modifier. Using a fluid without the modifier in the electronically controlled Z-51 diffs can screw up the traction control apparently. My non-electronic traction control in the base Stingray doesn't need the modifier in the differential. You can use the standard GM fluid out of the bottle or choose another brand and add the modifier from a source such as Summit Racing.
It's a messy job but not overly difficult as long as the car is level when draining trans/differential and adding the new stuff to both. You pretty much have to have the car on a lift to achieve the level status. It won't be level enough if raising one end on ramps, for example.
LateLifeCrisis
I did the differential fluid on my 2019 when it was 3 years old. Had my garage use the original Delco fluid - it's important to use a fluid that has the LSD friction additive. Fluid is below. For the M7 fluid change, just getting that done for the first time later in May (at age 5 1/2). Going to stick with Delco fluid for that also.
