Hurst T56 Magnum Shifter Exploded View of Design

[jorgezee1]

Hello PT people,

I decided to document taking apart my Hurst Magnum shifter to see if there is anything I can do to help seal it a bit better in case in the future it starts to leak. There are several threads on here previously documenting leaks. The most recent one from BobinFL - https://www.pro-touring.com/threads/...ng-T56-Shifter

This is just to show what I found and if you guys can chime in on what you think can be done or not done.

I should note that this is something I have not personally experienced yet. I cannot say it will leak, but for the sake of just tinkering I decided to investigate this a bit more. I have used the std t56 Hurst billet shifter and I do like the feel, so I really hope to use this shifter in the Magnum.

BlackJack Hurst T56 Magnum Shifter:

In the pictures you will see how loose the seal is to the shifter ball shaft. I think this over time will cause fluid to push through, but it should also let the fluid drain back. The pivot ball from my view would create the positive seal to keep any fluid from coming out. At least this is what I think will happen. Now there are reports of leaking shifters, so my guess is the wear in the pivot ball and the underneath seal start to deteriorate causing it to leak.



Another contributing factor is on a 1st gen Camaro they have you place the shifter in the forward position which will expose teh seal to more fluid.

















The seal used is very similar to that of the stock t56 and billet plus shifter. Close enough that you can fit and I would say use it as a replacement if needed.





Hurst OEM and Billet Plus Shifter:

In comparison Here is the Billet Plus Shifter and a Stock t56 Shifter. I have rebuilt them several of them through the years. These are some pics I took a few years ago.
In the OEM and Billet plus application the pivot ball shaft is larger and the seal provides a better fit.













Looks like possibly adding material via heat shrink or other to help seal was my first thought, but as pointed out in another thread, it may not survive the heat cycles and trans fluid very long.
Any thoughts?

[jorgezee1]

Found this on McMasters website. Looks promising. What do you think about adding heat shrink over the pivot shaft and seal?

https://www.mcmaster.com/heat-shrink-tubing

Another Alternative is to machine a grove on the shaft to accept a spring clip or similar to mechanically hold it in place.

[BobinFL]

A couple of things i noticed with mine, is that the higher up the shift shaft the seal rides the less likely it is to be deformed as the amount of movement of the shift shaft is less closer to the pivot point, so if there was a way to hold it higher up towards the pivot point that might reduce the stress on the seal opening. If the seal design was modified so the end had a lip molded in and a corresponding groove cut in the shift shaft for that lip to seat in that would help. I wondered if a small zip tie around the end of the seal, maybe even with a small groove or depression cut in the shaft would be enough to seal it better.

My issue was that the fluid that got past the seal and the ball pooled up in the upper dust boot, until there was enough and then is started to leak out around the dust boot. I went with a different design shifter and that has solved the issue for me.

Good luck

[jorgezee1]

A couple of things i noticed with mine, is that the higher up the shift shaft the seal rides the less likely it is to be deformed as the amount of movement of the shift shaft is less closer to the pivot point, so if there was a way to hold it higher up towards the pivot point that might reduce the stress on the seal opening. If the seal design was modified so the end had a lip molded in and a corresponding groove cut in the shift shaft for that lip to seat in that would help. I wondered if a small zip tie around the end of the seal, maybe even with a small groove or depression cut in the shaft would be enough to seal it better.

My issue was that the fluid that got past the seal and the ball pooled up in the upper dust boot, until there was enough and then is started to leak out around the dust boot. I went with a different design shifter and that has solved the issue for me.

Good luck

Bob, I had the same idea. The further up you go the better fit but still not quite enough to seal without something to help it.


I played around with a few ideas and I think I found one that might work. No real way to tell until it in the car.

Only my theory...

Looking at the way the oem shifter were designed the seal really needs to be a tight fit to help keep fluid from being pushed into the assembly. These oem shifter are not known to leak (to my knowledge), but they also do not have a drive gear under them like under certain applications with the magnum.

Possibly when the initial leak problem started/reported and no seal was used on the Hurst magnum shifter, they? went into parts bin and modified the shifter to accept the oem style shifter seal or billet plus shifter seal. This may have proven to help slow down trans fluid entering the shifter body just enough to call it good... At least from the shifter I have it appears it was not quite the right size. The seal is just to big to properly seal fluid out. Another solution could be to enlarge the shaft diameter to better suit the seal (new tooling) or make a new seal with smaller diameter (new tooling) both would possibly be expensive solutions. Not sure and I don't think we will ever know.

I first thought about adding a shrink tube to help clamp it down, than I though about inverting the seal as it would seal better at the top, but that might cause more of a fluid to get pushed into the body and no way to drain back.

So, I took the seal out and after a few version of modifying it to work I came up with a seal hack... Literally took an old seal and cut it. Than just added it to the original one. The idea here is the seal will ride up high enough that it will seal against where the shaft and pivot ball meet. This would be a secondary seal to keep it from entering the body. The lower seal is still somewhat open, but that's ok, from my view if fluid enters the cavity between the two seal it can still drain back. I will add rtv to both seal where they meet. This should hopefully prevent bleeding into the body from that point.
















I am not sure this will work, but it's worth a shot. I already have the shifter and I would hate to spend another 300-400 on a new one.

Let me know what you guys think!

If you have this shifter and want to try this, the seals can be purchased for about 5.00 from Core-shifters

https://core-shifters.com/collection...nt=19996478342

[BobinFL]

That is some nice out of the box thinking. That just might work. Simple and cheap to do. However, in my case it means disassembling quite a bit of the interior to get to the top of the trans. Seats, console, carpeting, sill plates, etc. Having done that 4 times now since the trans went in, and the Bowler unit is not leaking, I am probably not going to experiment any further. Unless we get locked down again and i get bored, then you never know.

[badazz81z28]

Is it worth it? Is that shifter better than the one that comes with the Magnum?

[jorgezee1]

Is it worth it? Is that shifter better than the one that comes with the Magnum?

I don't know... I purchased the shifter long ago and just started to build the car. I am not sure if I should just abandon the Hurst shifter or not. Since I already have it, I decided to play around with it, either it will work or it wont. I could use the stock tremec shifter or buy a Bowler Shifter.

Actually Carl C mentioned that the Tremec shifter is pretty good, only trouble is the seal that seems to go bad. He modified his to help keep the seal "happy" so I may visit this as well.
I also sent a PM to Craig from Bowler to see how much it would cost me to get one of those.

We will see... I have the speedtech tunnel patch. I might modify it so that I can have access to the shifter for servicing/swapping or I just buy the Bowler shifter and be done.....

[badazz81z28]

I don't know... I purchased the shifter long ago and just started to build the car. I am not sure if I should just abandon the Hurst shifter or not. Since I already have it, I decided to play around with it, either it will work or it wont. I could use the stock tremec shifter or buy a Bowler Shifter.

Actually Carl C mentioned that the Tremec shifter is pretty good, only trouble is the seal that seems to go bad. He modified his to help keep the seal "happy" so I may visit this as well.
I also sent a PM to Craig from Bowler to see how much it would cost me to get one of those.

We will see... I have the speedtech tunnel patch. I might modify it so that I can have access to the shifter for servicing/swapping or I just buy the Bowler shifter and be done.....

I ask because Im looking to buy one....I have been running the stock shifter just fine, but wouldnt complain about a little shorter throw.

[jorgezee1]

I ask because Im looking to buy one....I have been running the stock shifter just fine, but wouldnt complain about a little shorter throw.

would you like to test the Hurst shifter? I would like to see if the seal works. Id be willing to ship my shifter to you to test it out. I’m still not ready for my swap. I figure I am at least 4-6 months from starting.

let me know.

[BobinFL]

Jody gave me a tip to put in a removable plate in the tunnel patch big enough to remove and/or service the shifter. I am SO glad i did that, and recommend you do the same. Easy enough to do when the interior is out and if you ever need to get back into the shifter for any reason in the future that removable patch will be essential.