2008 GT500 Diff Leak after tracking or agressive driving. Help ???

Discussion in '2007 - 2014 Shelby GT500 Tech' started by jjjamn, Dec 27, 2008.

  1. 2008 GT500 Diff Leak after tracking or agressive driving.

    I am running a 08 GT500 with a Saleen Watts Link on the rear (Dont think this is the issue). After my first track day I noticed lots of diff fluid leaking or dripping off the rear diff after 10-15 laps at Laguna Seca. I took 5-10 more laps and then called it quits because of the amount of diff fluid leaking from the breather on top of the rear diff.

    I took the Shelby to the dealer for further inspection and they mentioned that the fluid might be too high because its leaking out the breather on the top of the diff cover. I had the level corrected and went back to Laguna today. After 5-10 laps I had diff fluid dripping from the read diff/axel again and called it quits.

    I have the shelby in the shop again and I guess I will just have a hose and overflow/catch can installed????????

    Any others with info or solutions? I have read many others with this problem but no solutions yet?

    Thanks in advance.
  2. Do you know how hot your rear differential fluid is getting? What weight rear gear oil are you using? Is the fluid cooking off?

    Have you considered a rear diff temp gauge or a rear diff cooler yet? Check out Maximum Motorsports - they have a handy selection of parts...


    Also, read the following thread over on SVTPerformance - it covers much about rear diff cooling for Cobra R's that are open tracking (helpful info, regardless of your application):

    Rear differential cooler - SVTPerformance

    The overflow/catch can route doesn't sound like a bad idea either...definitely do your research though. G'luck!
  3. update.

    ok so I heard that the KR's are comming stock with a differential fluid expansion tank. I just went down to look at one and indeed they have included an overflow on the new GT500 KR diff.

    I am looking to see if the KR's differential fluid expansion tank can be installed or I will just get something fabracated for mine.
  4. Turn off the traction control and you should be fine.

    I had my new 08 GT at Nashville speedway and just about every new Mustang had the same problem. It was just not GT500s. It was GTs, Roush, and GT500s. We were told that if the traction control was turned off, it would not heat up as bad and the overflow would stop. Sure enough, it seemed to help. The track people were really concerned with us out there cause some cars were noted that the diff fluid splashing on the inside of the tires.

    There was a guy there that had a Roush 427R and he said that he was putting the catch can on his and already had it on his race car Roush 427R. He said the can was the only thing you could really do to solve the problem.
  5. Thanks for the input, I am in the process of installing the catch can now.
  6. would you mind posting some pictures of your setup when complete? My rear axle is a mess.
  7. KRs have a catch can as noted. The KRs and 11 svt perf pack cars have a finned rear diff cover with the vent hole located higher up, at the center of the diff, with a baffle behind it. That cover alone with the additional cooling and higher vent point may fix the problem, but you aren't going to be able to run it with the saleen cover.

    I've shot my diff cover after running sebring and it was about 180-200F