The Mustang Forum for Track & Racing Enthusiasts

Taking your Mustang to an open track/HPDE event for the first time? Do you race competitively? This forum is for you! Log in to remove most ads.

  • Welcome to the Ford Mustang forum built for owners of the Mustang GT350, BOSS 302, GT500, and all other S550, S197, SN95, Fox Body and older Mustangs set up for open track days, road racing, and/or autocross. Join our forum, interact with others, share your build, and help us strengthen this community!

Should I change Trans/Rear Diff fluid?

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

Just hit 1500 miles, did my first oil change at 1300. I'v read some talk of people changing out the transmission fluid and rear diff fluid at this point. Just curious why people feel the need to change gear oil that is so new?
Exp. Type
Exp. Level
10-20 Years
Depends if you are tracking the car or the Boss owner's manual. I believe it states that the first change should occur after 4 track hours or high speed events and subsequent changes every 12 hours for both the tranny and diff. I only have 4500 miles on my car and I have done the diff fluid twice and the tranny once. I switched to royal purple in both.
I had the same question JB. I have not tracked it yet but I have driven like I was on the track quite a bit. I think I will change evrything once I hit 30k. later this year just to be safe.

TMO Supporting Vendors

Buy TMO Apparel

Buy TMO Apparel