M6 tranny and diff fluid
 

I'll be having the fluids changed soon. I know there are better than OEM manual tranny fluids out there, but what about the diff? I've read that the OEM diff fluid is pretty good.

Recommendations on both? Thanks.

There is one poster on here that had problems with the Royal Purple Synchormax in his ZL1 1LE, but I put it in my regular ZL1 and love it. Shifts so much smoother than before.

As far as diff fluid, since I am still within my warranty, I put the factory recommended AC Delco fluid in. Seems to work just fine.

Thanks. Interesting about the RP fluid. I've only heard good things.

Another vote here for stock diff fluid but RP in the manual trans. The RP improved the way shifts feel tremendously.

Stock diff fluid and Redline D4 ATF for the M6. As others, I’m very happy with it over the stock fluid. It really smooths out the 2nd gear notchiness.

How many miles are you guys changing the M6 tranny fluid at?

I did the diff the first time at 1500 miles. Then I did the diff for the 2nd time AND the tranny fluid at 16,000.

OK. Thanks. I already did the diff at 1500. Only at 7000 miles so not close yet on the transmission.

Anyone have a link to the RP trans fluid?

Thanks

TREMEC makes their own fluid they recommend for their trannys now. i dont know about it but it may be worth a try.
https://www.tremec-store.com/collect...smission-fluid

I bought mine from Amazon...

https://www.amazon.com/Royal-Purple-...5-4be35d7258cc

About 7k miles. I was lazy and had the dealer do it when they were doing my track alignment.

I switched over to Royal Purple Synchormax and the shifts are great. They are even better when I run through the gears prior to driving. Like a pre lubing.

I also put RP diff fluid in the differential and it hasn't grenaded contrary to what I was told...:bonk:

Using RP in the trans and diff. 5500 track miles and no problems. I have changed the tranny fluid once and diff fluid twice during those miles and there is hardly any metal sludge on the metallic drain plugs on the diff and the tranny fluid looked like new. RP fluids have worked excellent so far in my car.