This is for those out there that “do it themselves”, and it should save you some money.

Venders ( Call these companies to order your parts. I all ready have figured out which is the cheapest. Order the following parts from each company, part numbers are in parentheses().. )
Parts List
1. Blumenthals (405)-232-9557
A. Viper Output Seal (16725) $7.41
B. Viper Tail Housing Bushing (BM29) $10.00
C. Main Shaft Bearing, front ( SET16) $12.39
D. Viper Speedo reluctor 10T (1386-110-003) 8.73
E. 30 Spline Spicer Yoke (short yoke/ 3-3-3931X) 61.28
F. U-Joint Viper to F-body Driveshaft (2-1153) 22.43


2. Six Speeds Inc (713)937-4411
A. Viper 30 Spline Main Shaft 225.00


3. D&D Performance (248)-735-6220
A. Viper Snap ring Kit 15.00


4. GM Dealership
A. GM Trany Silicone (97720043) 25.00


Parts Total = $387.24




Now for the Machine work. I had a hard time finding a place that had the machines to do the work.
I paid $140.00 for the machine work.
90.00 to cut down main shaft
60.00 bore out bushing
30.00 bore out seal

Refer to the pictures for help.

Machine Work
1. Remove tail housing from t-56
2. Take seal and bushing out of the old tail housing.

(Seal already out, stock bushing still in)

(Seal and bushing out, Notice the valley in the housing)

3. Notice the seal , and the stock “shorter” bushing.

The Machine shop will have to bore the tail housing out for the larger Viper bushing and , Viper seal. Also notice the small hole in the bushing, the viper bushing hole must line up the same. Other wise you won’t be able to add trany fluid when you are done.



4. Take the tail housing to the machine shop and have it machined to the following specs.
Seal machine for a .003” press fit
Bushing machine for a .003-.004” press fit ( .005” is kind of tight to press in, I recommend a little less)
Have the viper main shaft machined down 1.5” , or the same length as the stock shaft.( I did ¾” but 1.5” would be better), Note- You can cut the shaft with a chop saw , BUT if the threads are buggered it will be hard to slip on the new speedo reluctor gear. It may not slip on at all. I recommend Machining it, but a chop saw is cheaper.


5. After machine work is complete, take a dremmel, and notch out a bigger valley in the tail housing. You will notice there was one there Before machine work, but after there will not. So you have to make a valley to the trany fluid will flow into the trany from the shifter hole.


6. Install Viper bushing, keeping note of the trany filling hole, and the new valley in the tail housing. The new bushing is longer than the stock, go a head and install the new bushing all the way down, till it is flush.


7. Install Viper Seal.


8. Tail housing work is complete.

 

Install
9. Take apart t-56 completely
10. Reinstall all parts back on new Viper t-56 main shaft, Install new baring at this point.
11. Install new 10T Speedo reluctor gear, and the needed two snap rings.The stock t-56 shaft is smaller, thus the stock t-56 snap rings are smaller than the Viper. NOTE- stock is 17T you will have to have a retune on your pcm and have it change from 17T to 10T.

You could call D&D and order a 17T converted to a 30 spline shaft but it would raise the cost of the swap. And since most of the cars doing the swap will already have there cars tuned, it will not be much to have it retuned.

Total Cost =$527.24

That’s a lot cheaper than 900.00 and a 250.00 for a tail housing core deposit.


Good Luck to all pm for more pic's or help.

 

damn, that's some good info to have, thanks

 

One thing is that is to expensive for the machine work and the shaft. I have the shaft for $225 with free shipping and they should not charge you more than $50 to machine the mainshaft. It takes us about 15 minutes to cut a mainshaft, 30 minutes to bore the tailshaft housing and install the seals. This is very good info for the do it yourself guy but the machine work not everyone has the tooling to do.

Amber
Six Speeds Inc.

 

how much stronger would that acually make it? im gonna rebuld my t56 this winter, im a machinest some machine work wouuld be free. is it worth the trouble?

 

I dont have the tooling to machine these parts, but after the 7th machine shop i was ready to pay. The shaft price was with shipping, so i guess you are cheaper.

So, can customers send you there tail housings ready to be machined? Can they also buy the Viper main shaft already cut down for 275.00??


If you charge $50.00 for 15min worth of work do you charge $100.00 for 30 min?? Because then you would be higher than what i got mine for local.

Just trying to help out the "do it yourself guy", that doesn't have deap pockets.

 

a lot of machine shops charge a min fee. usually like 1 hr depending on the shop. i know my work charges 1hr min weather it takes 15mins or 45mins you pay for an hr. of chorse some shops may be different.

 

I believe this calls for a sticky!

 

that is really cool of you to do a write up like this. thanks!!!

 

awesome write up, another vote for sticky!

 

Your Welcome

I figured it was time to share some knowledge, thats what the forums are for.




ALSO

You can buy your rebuild parts from Blumenthals, they are cheaper than ebay. The only thing is i'm not sure if the block rings are the same quality as the supporting venders. But the gears and syncro's themselves are thremic, just cheaper.

 

I've done the mechanical speedo conversion on my T56 and would need a 7 tooth drive gear for the viper main shaft. Are these available?

I do a number of the speedo conversions and the viper conversion is common question for me. I just found this thread and if any or my customers for the speedo conversion want me to machine the tail housing to viper specs, this thread is pure gold to me!!! Thanks for sharing the info.

 

How much would you charge to machine the tail housing?

 

PM sent

 

Thanks for sharing this info... Great write up!!!

 

I saw you in gmht as LTX n/a champ nice, awesome write up

 

Good job on being able to complete a really good write-up to help us DIY guys while still giving credit to the vendors with the best deals as not to totally upset the balance of how the politics work on this board.

Now after being enlightened by the info you shared, I await the arrival of a vendor (not Amber at Six Speed Inc. because they are cool helpful people) to come in and tell us how doing it yourself is stupid and hurts trained professionals that have countless hours of training and $5000 tool kits for this kind of stuff. We are taking food off their table, lol.

Sorry for the rant but the above happens on too many threads on here, especially good threads like this. Thanks again for sharing!

 

Pretty nice writeup. Still for the extra $400, Ill let a pro do it. I guess i am not quite ready to rehab a tranny, lol.

 

Nice write up. Exactly what I was looking for

Is building a transmission REALLY as difficult as everyone says. Can it be compared to anything else on the car as far as difficulty goes? I'm willing to try but I don't want to get halfay through and give up.

 

From what I've read, its not difficult at all. Just a couple special tools. You need something like a gear puller, but it has to have extensions so to speak for the length of the main shaft, and your gonna need a press. Other than that, I don't think theres all that much to it.