Enter your username:
Do you want to login or register?
  • Forgot your password?

    Login / Register



    Results 1 to 16 of 16
    1. #1
      Join Date
      Jun 2018
      Location
      SW Florida
      Posts
      33

      Leaking T56 Shifter

      I have a T56 Magnum with a Hurst Blackjack shifter in the forward position. It is leaking up through the seal on the shift rod and out the outer boot bottom. It is in a 68 GM A Body. I believe it is the newer design Hurst, but am not absolutely sure. It was bought in 2020 from a reputable shop that does a good volume of business. I know there have been some issues like this in the past, but have not found any definitive fixes. Has anybody else had this problem, and if so, how did you get it fixed, or have you learned to live with it.

    2. #2
      Join Date
      Jun 2020
      Location
      Houston Tx
      Posts
      4
      Country Flag: United States
      Name:  3316E3DA-5D6C-4E6F-A85C-7DA8D99AA37C.jpeg
Views: 1270
Size:  117.7 KBThe stock shifter leaked on my T56. I’m glad I added an access panel to the top of my tunnel for easy access to the shifter plate. The rubber boot had slipped down the shaft to the recessed area above the shifter ball as shown on the left. The shifter on the right is from a tremec 600 which was a much better designed seal.

    3. #3
      Join Date
      Aug 2007
      Posts
      260
      Did you ever get any feedback on this? I have the same shiftier going in to the forward position in a 1st gen f body and I have also read about the leaking issues of the original units. With the new added seal, I thought this addressed that issue.

    4. #4
      Join Date
      Jun 2018
      Location
      SW Florida
      Posts
      33
      I am working with Jody, from Jody's transmissions. He is going to modify my Hurst shifter to hopefully make it seal better. I will be the beta test on this. Probably be a few weeks, but I will post my results.

    5. #5
      Join Date
      Aug 2007
      Posts
      260
      I am keeping on eye on this thread. Please let me know what they end up doing to fix the issue.

      I notice on the Blackjack the seal is not tight around the pivot ball shaft. I'm thinking if it can creep up through there. would it help to add a piece of heat shrink around the base of the seal?

      Here are a couple pics of my shifter.




    6. #6
      Join Date
      Jun 2018
      Location
      SW Florida
      Posts
      33
      The current thinking is that the seal is stretched tight over the shift rod, and successive heat cool cycles allows the rubber to deform or otherwise not seal as tight as it should. With a driven gear right under the shifter when the shifter is in the forward position the velocity of the oil coming off that gear is allowing oil to get past the seal. We are looking at modifying the shift rod to maybe create a groove to let the seal sit in. Possibly with some form of mechanical clamp, like a pinch type clamp used on CV boots. Heat shrink is another good idea, provided it will survive in that environment and be compatible with the trans oil.



    7. #7
      Join Date
      Jul 2008
      Posts
      453
      Country Flag: United States
      I've got the same issue with a b&m ripper shifter. I was going to clean/dry surfaces with red brakleen then try safety wire to try and seal the boot against the shift rod. Might throw a skim coat of ultra black rtv for good measure.
      *Jeff*
      Project Salty - 1964 4 door Malibu, beaten, neglected, red headed foster child
      Cammed LQ4 / T56 Swap Project Thread <-click to read! 😁

    8. #8
      Join Date
      Aug 2007
      Posts
      260
      Any update on this?

    9. #9
      Join Date
      Jun 2018
      Location
      SW Florida
      Posts
      33
      Have been testing and it appears using a sealant around the top boot is working. No leaks so far with more than 800 miles on. Updated shifter is still in the works.

    10. #10
      Join Date
      Jun 2018
      Location
      SW Florida
      Posts
      33
      Update - Trying to seal the outer boot to the shifter has not worked. The unit is leaking worse now than ever. I have formally requested, in writing, that Holley / Hurst provide assistance to resolve this issue. Am awaiting their reply and will update once that is received. Hurst may have two different seal designs, and it appears they are still selling the initial, and prone to be leaky , design in their replacement shifters.

    11. #11
      Join Date
      May 2018
      Location
      way east on a rock
      Posts
      155
      just by casual glance, that's a horrible design. There's a bunch of ways they could make that better, not sure you could make it much worse. I would like to know what their thinking was behind that design, it looks like somethings missing

    12. #12
      Join Date
      Feb 2008
      Posts
      126
      American Powertrain worked thru their own issues with their White Lightning shifter and sealing problems. Their 3rd gen has seemed to solved the issues they were having very similar to the Blackjack shifter and its design.
      '69 Camaro RS/SS "Mercury Rising"

      for more build pics - Instagram @cfxlr8

    13. #13
      Join Date
      Jun 2018
      Location
      SW Florida
      Posts
      33
      Spoke with Hurst yesterday, and they stated this is the very first incident they have heard of with their shifter leaking since 2012 when they added the seal. It appears earlier shifters had no seal at all. The Hurst design is very close to the Tremec shifter original to the transmission. They want me to try to replace the seal. In my opinion it is a flawed design, and will continue to be leak prone. Am evaluating options, and looking at the Bowler unit, which seems to have a good seal design Based on my research it appears most of Hurst's competitors have directly addressed the leaking seal design.

    14. #14
      Join Date
      Jun 2018
      Location
      SW Florida
      Posts
      33
      Further update
      When I pulled the shifter out again the upper section of the shifter under the outer dust boot was literally full of trans fluid. That fluid was leaking out around the dust boot and causing the leak on by garage floor. Obviously the oil had come up past the shift rod seal. It seems after some use the seal around the shift rod inside the trans must become elongated at the bottom, and almost acts like a scoop for the oil. This elongation appears to occur over some time as the shifter moves front and back and side to side, and since the seal is just stretched around the shift rod there is no way to prevent this from occurring. You could possibly put a clamp or do a roadkill zip tie moment on the seal end, or use some heat shrink, as was suggested. Possibly if there were a groove in the shift rod and an O-ring molded into the end of the seal that could snap into the groove then the Hurst seal design would work better.

      Hurst responded to my requests for help, but I have decided to not use their shifter going forward. I have gone with the Bowler shifter, which has a better seal design, in my opinion. The downside to the Bowler unit is that it has slightly longer shift throws than the Hurst unit. The shift throws with the Bowler unit are about the same as the original Muncie 4 speed, whereas the Hurst throws were probably 30-40% shorter. The benefits with the Bowler unit beyond having a different seal design, is that the shifts are also smoother. The Hurst unit clicks into gear, whereas the Bowler unit has a more "velvety" yet positive feel to the shift quality. If you are racing, and banging gears, and the potential for a little leaking oil is not a concern, again, just in my opinion, the Hurst is a good recommendation. If you are driving or cruising I would recommend considering the Bowler unit for sure. Others have used the Hurst unit and had no oil leak issues, but that has not been my personal experience. I have no experience with the American Powertrain shifter, but it looks interesting.

      I have to say that once I got their attention Hurst's customer service was top notch. I have no complaints with how i was treated, and would definitely do business with them again. They absolutely stand behind their products. The only reason I decided to switch to the Bowler unit was my perception it has a superior seal design and a personal goal to be done with mopping up trans fluid from the garage floor after a cruise. I just was not confident I would reach that goal with the current Hurst seal design.

    15. #15
      Join Date
      Feb 2016
      Posts
      3
      Exact same response I got from Hurst back in September... they ended up shipping out a new blackjack which leaked just as bad as the first one (and the stock tremec shifter). I tried replacing the check valve on the vent tube thinking the old valve wasn't releasing at 10lbs of pressure, but same leak. I assume that the only way to stop the blackjack from leaking is to flip it to the rear position or remove the check valve and have an open filter (which I heard may lead to leaks in the tail shaft. Really not understanding how this isn't an issue for anyone running the shifter in the forward position.

      -Adam

    16. #16
      Join Date
      Jun 2001
      Location
      Newbury Park, CA
      Posts
      5,821
      Country Flag: United States
      The Magnum OE lower boot interface is an awful design. The lower boot becomes severely overstretched, hence causing it to crack and leak. I've had two do this with one replaced under warranty. The fix was to machine the shaft so that the lower boot shaft sealing surface has a much more reasonable interference fit. After three years it has worked fine with no leaks.

      Unfortunately Tremec will not sell just the lower boot, so if yours cracks, you're SOL. Very poor design of such a simple part.

      Though I've not had one in my hands yet the Bowler part looks very promising with its Viper inspired spherical ball design and fewer leak pathways.
      VaporWorx. We Give You Gas http://www.vaporworx.com





    Advertise on Pro-Touring.com