Hey everyone, I have a quick question about getting my tranny oil changed. I did a search but couldn’t find the answer I was looking for.

So my car has been shifting not so smooth lately, I want to try some Redline or Royal Purple fluid. I called a transmission place today and the guy said something about me needing 12 quarts? I think he was going to completely flush it out.

I don’t need it completely flushed out, do I? How many quarts of oil should I bring?

Thanks for your time.

 

It must be an automatic, right?

12 quarts of Redline is overkill! I would just use good name-brand tranny juice.

S

 

mazda swapped it out for me and only used 2 quarts of the transmission fluid and 2 quarts of the differential both redline. You can look at the car manual and i believe one is 1.4L in size and the other is 1.7L. assuming the car is a stick

 

12 quarts is absurd. You don't need it flushed out; just drain the oil that's in there and replace it.

I replaced my manual trans fluid with Royal Purple and it required just over 2 qts; get 3 bottles and that will cover it just fine. The rear differential requires just under 2 qts so if you want to replace both, get 5 bottles and that will take care of it.

 

thanks for the replies. my car is a manual. When you take your car somewhere to have the tranny fluid changed, do they automatically do the differential as well?

thanks.

 

No.

 

ohh. Sorry if this is a dumb question, but do both the tranny and differential use the same oil? is 75W90 the correct grade of oil? I was looking at redline online, and they have the 75w90 and the MTL.. I'm confused as to what I should buy.

thanks for the help

 

You need to make sure that the differential oil is suitable for a limited slip differential, assuming you have the 6-speed manual GT version of the car.

 

Check out the DIY thread https://www.rx8club.com/series-i-do-yourself-forum-73/diy-transmission-differential-fluid-replacement-35115/

Post 46 shows what to get.