Hello,

I have a Viper T56 with fbody front plate, tail housing, and bell housing. I bought the transmission without the output bushing or seal. The owner assured me that all the transmission was bored for a viper bushing and seal and only needed an output shaft bushing and seal to be complete. Recently I purchased a Timken 5206 seal kit from Autozone and tried to install it today. The bushing install went fine, but unfortunately I have been unable to find how far into the tail housing the output shaft bushing needs to be pressed in. The best information I can get is that it needs to be installed "flush," but flush with what? The last lip of the tail housing or the inner 'cup' of the tail housing? I'm in a pretty bad situation because I received the transmission without a bushing installed so I have no reference for how it was installed.

Here's how I assumed it needed to be installed:




In this picture you can see that the bushing is installed so that it's upper lip is poking up about 1cm above the inner cup of the output shaft end of the tailhousing. I figured it needed to be done this way because the output shaft seal seems to be the right diameter to fit around the bushing, or at least the part highlighted in the following picture:



The seal seems to fit around to bushing without too much trouble, but it will NOT press down and stay down in the tail housing. Shown here:



If I push it down, the rubber in the seal just collapses, but it's elastic enough to unseat the seal after I remove the pressure keeping it in place.


I really don't know what to do at this point. I'm pretty convinced that I'm doing something major wrong, so I went ahead and posted the pictures so hopefully someone can point out what I'm doing wrong.

Lane

 

The red part of the seal is what presses into the transmission.
The "foreskin" of the seal goes outwards.

The bushing could be pressed further in. If 100% of the front to back length of the bushing is pressed into tailhousing, you're good. So if the rearmost end of the bushing is flush with the section of tailhousing into which it's pressed, that's ideal (so it also gives good contact to the slip-yoke.

Great job posting pics.

Post more.

PS: I hope that seal fits that machined(?) tailhousing...

 

^^^ x2

And you may have to do a final hone to the ID of the bushing to get the yoke to fit correctly. Have you tested that fitment yet?

 

Thank you guys. I was afraid that was the problem. Unfortunately the diameter of the red end of the seal is much larger than the opening of the tail housing, which is what threw me off in the first place
It probably will need to be honed again like you said Mike.
No fun for me because I live in the Mississippi sticks and finding a good machine shop is basically impossible. Guess I'll start looking for a shop I can send this puppy to, because it's not going to get done locally.

Thanks again for your help
Lane

PS
Here's the only other pic I took yesterday:


It's going on a 6.2L stroked and forged LS1 with patriot heads and cam. Hoping to get 500HP to the wheels of my 93 Mazda RX7 out of it

 

It may be the picture (seal upside down in tailhousing) is deceiving, but it looks like the seal would be a perfect fit and that the tailhousing seal area is machined correctly? Can you get a set of set of calipers and measure the seal OD and the tailhousing seal area ID ? The seal will have some crush built into it so that it seals correctly. Does your viper slip-yoke fit the seal correctly? I know the SRT-10 truck version of the T56 used a larger bushing/seal/yoke than the viper.

(Also odd that you have a viper main case as shown by the 2 top studs, but the F-body extension shaft instead of the viper 1pc counter-extension.)

I'd love to see a pic of the mid-plate and input shaft if you don't mind..

 

Unfortunately, I'm at work and these are the only two images I have of the transmission on hand:




Supposedly, this transmission has a fbody input shaft too. Anything you'd like to add is very valuable to me as I am pretty much a transmission newb, especially with T56's.

I'll break out the calipers and try to take measurements soon. I did put the seal the against the tail housing in the proper direction a couple of times to see if it felt like an option, but my first impression was that it was too large even with some 'crush.' Nothing like the bushing. The bushing had beveled edges that seemed to want to go into the tail housing.

Thanks for the advice / help.

Lane

PS
I haven't had my axle made yet so I don't have a slip yoke to try.
Also, my transmission wasn't in the dirt for long in the above pics. Ever since that pic it's been bagged and taped

 

OK Gents. Here are the numbers:

The tail housing seal diameter = 60.12-60.27mm
The seal's OD = 63.48-63.59mm

So about 3.5mm difference in diameters. Of course, this was all measured with a Harbor Freight $10 caliper, so take those numbers with a grain of salt...

I still think it's too big to force in, but I'll give it a shot if you guys think it will crush down small enough to fit. Otherwise, I'll find someone I can ship it to, to redo the machine work.

Thanks for the advice guys

Lane

 

If you have any questions about doing a viper t56 in an fbody. Feel free to give me a call at 209-559-7342. C. J.

 

No, that 60.12mm tail housing seal is stock sized, so it appears they never finished the job. (In addition to not machining off the end of the output shaft either)

My $0.02, by the looks of the RTV seeping from the mid-plate - main case joint, you'd be well advised to tear it completely apart anyway to have it gone through completely.

Here's another thread for you to read through and maybe give to a shop if you decide to send the trans out for finishing:

https://ls1tech.com/forums/manual-tr...-write-up.html

 

Why not just share your advice with us all? One big happy family here...

 

Thanks for the link Mike. I've used that tutorial in particular as my bible throughout this ordeal. Unfortunately, they don't give bore diameters or clear pictures on how the output shaft seal is installed. They also don't go into detail about how to seal the tail housing to the main case.

I agree that the RTV looks sloppy on my transmission, but I don't know if it's 'seeping.' The transmission was supposedly rebuilt by a transmission shop in a neighboring town. As part of the rebuild, a complete syncro rebuild kit bearing kit from D&D Performance was supposed to be installed. This transmission hasn't been installed or used since it came from the shop and I bought it, so I would think the RTV was just a sloppy install.... Still, I'm not opposed to sending the transmission off to be finished. I'd just want to find a good place that would be willing to 'check over' another persons work.

Have any suggestions?

Lane