I contacted a rep at Royal Purple today to find out what fluid to use when I change my gearbox oil this weekend, since nobody around here sells redline. I mentioned that redline MTL was what a lot of people around here use, and getting my engine oil and gear oil viscosities mixed up, I incorrectly told him that I thought MTL was like a 75W oil. He corrected me, telling me it is a 5w30 or 10w30 oil, and that Royal Purple 5w30 engine oil is what to put in my mini. He also said that Detroit Tuned uses this oil in cars, and has no issues. He seemed pretty sure of himself, but I wanted to post on here to see what people thought and if anyone uses any other kind of RP fluid for the 6 speed trans.

 

The redline says it is a 75w transmission oil which is equivalent to a 5w30 engine oil. I was surprised at how thin it was.

 

I've been using RP for awhile now. Seems to work just fine.

Nik

 

You use the 5w30?

 

Syncromax, not sure the weight, but seems about the same as 5w30.

Nik

 

As I was told it protects at 75W but pours at 5W30. It sounded good

 

Well, RP assured me I could call with any problems, so I'm assuming "my transmission ate itself on your own oil recommendation." wouldn't be an issue.

 

Haven't used their tranny fluid yet Max, but I use their oil, but I use 5w40 because it meets the BMW LL01 standard. I never wait that long to change it anyway, but it's a little piece of mind that I enjoy.
Their oil has proven to be wonderful, the car has felt great since I made the switch to RP.

 

I think that there is a different scale for transmission fluids and engine oil. Because they all seem to say that it is a 75w transmission fluid OR a 5w30 engine oil.

 

Does anyone know how much do we need for a flush?

 

Does anyone know how much do we need for a flush?

if you have a 6 speed manual and are draining and replacing 2 quarts is what you need to buy.

 

I was amazed at how much quieter and smooth the lower unit was after changing to their gear oil for marine use in my boat, it would have to be great in the transmission too. Heck you might even want to try it in the rear end.........just kidding RP really is great stuff.