Markg#76

I have a 1976 corvette with a L-48 transmission, I need to add transmission fluid but have no idea what kind it takes. I believe it use to be Dextron 3 but a lot of auto stores are telling me I can also use Dextron 6 now which is the same as the old Dextron 3, not sure which one to buy, any suggestions would be appreciated..

Eric P

Dex/merc or Dexron 3 will be fine, you don't need the Dexron 6

Markg#76

The guy at auto zone told me good luck trying to find Dexron 3 and tried selling me Dexron 6 for $10 a quart. I knew they still made Dexron 3, have no idea why he said that the Dexron 6 replaces the 3.

Bikespace

Uh, L48 is probably your engine. Just to be clear, do you have a TH-350 3-speed automatic transmission, or a 4-speed manual transmission?

Motorvation

Red and slippery. Add a bottle of Lubegard red. Or if there’s a leak problem, add some Lucas Extend.
https://www.lucasoil.com/product/aut...d-conditioner/
https://www.lubegard.com/products/platinum/
I’ve used either depending on the situation. Lubegard to smooth the trans operation, enhances shifts. Best additive since Trans-X.
Lucas has the stuff (MEK) to swell seals and slow leaks.

Steve O.

I did assume automatic, too….

Mdbirk

Walmart, just under $20 for a gallon. Use it in my wife's 66 Pontiac. States dexron III. Dexron-VI is compatible with older vehicles whose automatic transmission uses the earlier versions of Dexron.

​​The main difference between Dexron 3 and 6 is that, the Dexron 3 is a regular ATF and the Dexron 6 is the upgraded and synthetic automatic transmission fluid. 6 has better foam resistance and sheer stability.

Jud Chapin

I like Mobil 1 synthetic atf that meets Dexron requirements. Among other benefits, it handles heat much better than the standard atf.