EDIT: Changed thread title to indicate my Torque Arm and Crossmember solution for Aftermarket T-56 transmission.(NOT 4th Gen T-56)

I have an aftermarket T-56 and standard duty Spohn Cross Member and standard duty torque arm that I installed about 22 years ago. I recently noticed The part that connects to the differential, the two flat 1/4" plates top and bottom are starting to bend.

As we know, the aftermarket T-56 uses the stock T-5 clutch, flywheel and bellhousing, which moves the torque arm back about 2 inches, so an off the shelf replacement torque arm will not work. EDIT: Or will an off the shelf work...

As I said before my rear end mounting plate on TA is bending. I could just buy a new rear end mounting bracket, but I'm sure that will start bending too. So I contacted Spohn and asked about a Pro Series version. They told me the following: We no longer offer that kit as Tremec stopped making that transmission many years ago. All of our 82-92 kits use the same torque arm EXCEPT the kit you have, that requires a shorter arm. We do not have a Pro-Series arm that would work, sorry!" Then I asked about a custom made version and got this response: "We can't make those a custom length because the tubes run on angles and take a complex jig for assembly and coping the tubes. When you change the length all of the angles changes."

So all the torque arms they have now use the same length, which he would not tell me the length. I measured from the poly bushing mounting hole to the first differential mount bolt hole. I got about 47". For everyone who has a Spohn torque arm and cross member, can you get me this dimension. I would guess it would need to be the recent design, maybe 2015 and up.

According to the pictures of their Pro Series crossmember/torque combo for the 2004r (shown below) or a turbo 400 swap, it looks like it would be a shorter TA that would work for me, close to 47".


The pic below is the exact crossmember and torque arm I have. You can see where I measured and got 47".

EDIT: I have moved on from Spohn and went with off the shelf UMI adjustable Torque Arm, similar in design to Spohn Pro Series. It is a transmission tail-shaft clamshell mount for quiet and clunk free operation. I modified it to fit Aftermarket T-56.

 

I had a local speed shop make me a torque arm.

UMI sells a heavy-duty bracket to mate to the axle. Then you just get the shop to fabricate the bars with spherical joints that thread in, and it will all mate together.

You can see a picture of mine during construction in Post #789, https://www.thirdgen.org/forums/ltx-...ml#post6149848
Nevermind that the bracket is installed backwards in the photo... LOL! It was just a photo, not how it actually mounted in the car.

Better picture of bracket in Post #4 of this thread, https://www.thirdgen.org/forums/ltx-...ml#post6455996

 

Thanks QuickTrip for the links. Good information. And yes, I too can't stand the vibration and clunking felt in the body with this type of torque arm mounts.

I swear, I really think the Spohn Torque Arm they use across all their crossmember/torque arm product versions will work. I really want that length dimension.

 

If your torque arm is fine and only the bracket needs beefing up, then maybe see if you have luck with the UMI bracket interchanging? I have my original UMI torque arm to measure the spread between upper and lower mount if you like.

 

Thanks QwkTrip. I don't think the brackets will interchange. The pic I posted above with the 47" measurement is the exact setup I have. You can see the spread between the tubes is very small and fit in between the bracket ends. In this design most of the force is on the differential bracket. The Spohn pro series and UMI moves the lower tube to the other side of the lower bracket for a better spread of the vertical force.

 

Is it impossible to take the torque arm and bracket to a fabricator and have them build you a new bracket or arm?? Since they don't make yours anymore you've got to spend money now

 

I may have an off the shelf option. An investigation has been opened...

 

Any update?

Edit: Thanks for the update.

 

I shortened my Spohn arm by cutting it and sleeving it. Its got 20,000 miles on it now at 750 whp.

 

UPDATE:
After an extensive search for a replacement torque arm, I went with UMI part number 2205. It is a transmission mounted adjustable torque arm for factory length transmissions. (52" from the transmission end to the first differential mount bolt hole.

I really wanted to move away from crossmember mounted arms as they just bang and make way too much noise for a car that will be driven 95% of the time on the street.

So I sent UMI tech a few Emails for some dimensions where the transmission clamshell bushing mounts. I found out there is enough tube length from the tube end, to where the weld starts for the other tube. (Tech said 5.135" I actually measured almost 6").

I shortened arm by 1.9", cut out the tube end cap from cut off end and rewelded it to new length torque arm. A little grinding, added some paint, done. There is also some length adjustability on rod eye mounts to differential bracket. (around 0.5" or so safely)

Fitment is good. Slight interference with bracket screw in tunnel that holds brake and fuel lines, just used a smaller headed screw. Used my original T-5 clamshell bushing mount to transmission. Last thing is modifying Spohn crossmember to remove old TA mount. This where I'm currently at now. Need to paint crossmember and install.