The Stovebolt Site Forums The Shop Area Driveline Installing a T-5 transmission

I know of lot of 50's Chevy truck owners install a T-5 transmission and I am told the trans has to be modded to fit. Anyone know what needs to be done? I believe if I recall that the input shaft is too long. Can it be cut off, or an adapter plate added for spacing? Would a spacer prevent the clutch from working right or would there need to be other mods? Any help would be appreciated. The truck I have is a '54 3600 with an SM-420 transmission I want to remove. 261 CID engine.

There has been a bunch of chatter about this on this website.

You will find a lot of info by doing a search. Basically, yes you have to cut off the end of the input shaft & the brg. retainer collar. Use the old trans as a guide. You need to cut the splines that the clutch disc rides on back about 1/2 in. to keep the disc from hanging up. The best way to do this is slid the disc on till it stops. Mark it on the shaft & grind the grooves till it goes back about 1/2 in. A cutoff wheel works good for this. Drill out the mounting holes to 1/2 in.

Search "Lugnutz". His blog covers it all. He is very helpful via PM if you run into trouble along the way. If I ever do another one, I will spring for the aluminum spacer plate. That eliminates many of the modifications.
Carl

Thanks! I'll do a bit more research and then decide how to go about it.

Oldie, this is his T-5 blog. I highly recommend it.

http://lugnutz65chevystepside.weebly.com/t5-info-page.html

Looks like I need an adapter plate to make this work. I'm not a big transmission guy, but will this throw off my clutch throw distance? Can I use a hydraulic clutch with this set up? It looks like I need to use my stock bell housing rather than the S-10 bell housing with the adapter to make the input shaft fit right. Anybody know if I am understanding this correctly?

I installed a t-5 on my 54 several years ago, I didn't need an adapter, just did the modifications that Wrenchbender mentioned. I shorten the input shaft, opened up the mounting holes to 1/2 inch and cut the splines back on the input shaft using a Dremel with a couple of cutoff discs mounted back to back to get the correct spine width.

I used the stock bell housing. I also cut the bearing retainer collar as Wrenchbender mentioned.

I used an adapter plate from Hamilton Intakes. Why? Because this is my daily driver, and it's not unuasual to find me hundreds of miles from home. In the event the tranny fails, I want to be able replace it with a junkyard spare with out doing roadside mods with a hacksaw.

The spacer does not affect how the clutch works.

Get rid of the original trans cross member. You don't need one with the T-5.

Twotone, did you remove your bolt-on transmission crossmember? Did it interfere with your T-5? Mine didn't, so I left it in place. I did remove the original bracket/mount which attached to the torque tube ball, and I did not try to support the T-5 tail end to that crossmember. It just hangs out there just like it did when it was in an S10. I wanted to keep the crossmember to keep the frame stiffened up. They are so flexible to begin with.
Carl

I did remove it. I had read that it should be removed due to clearance issues, and because it would not be used. After the swap it looked to me like there would be no clearance issues and in fact kept the cross member with the thought of reinstalling it for the same reason you left yours in.

I feel like I've done something wrong here. My T-5 trans is 13-52-145 which translates to 85-86 S-10 V6. I tried it in my '54 with the stock bell housing to check the spacing and it bolted right up. I didn't force it, I put the bolts in by hand and just did the last bit with a wrench. I can put it in gear and turn the output shaft by hand. I don't see the need for the adapter plate. Am I missing something here? HELP!!

I wonder if yours had previously been modified for a similar application (mounting holes opened up, input shaft shortened).

I guess that is a possibility, but I wouldn't know how to tell. As is, it seems to work, but I'd hate to install it and have it tear everything up. Just want to do it right. I got the tranny from another hotrodder who had an idea for a project that he never started, just needed to clear out his garage and I was in the right place at the right time.

Wow. Any chance you can get ahold of the previous owner? If he had plans to use it for a hot rod project, there's a good chance he's already modified it. You may have just gotten lucky.

Clearly it was already modified. The mounting holes are metric and need to be enlarged to 1/2", just for starters.

Sounds like you are right that it is already modded. I took the bolts out of the SM-420 and used them in the T-5. The only difference was the T-5 doesn't have threaded holes on the bottom, so I will need to use a nut and bolt.

Oldie,
I am a self proclaimed T5 enthusiast. I can help you figure out what has been modified on your T5. I've personally done just about every mod possible except a few.
Chances are the seller had it ready to bolt up and saved you the hassle of figuring out the details.
Send me a PM and we can swap email addresses.
Jay

Take Lugnutz up on his offer! I couldn't have put my T-5 in without his generous help.
Carl

I just put mine together and have to figure out what to do for clutch fork travel. I ran the adjustment out as far as it will go and push the pedal to the floor and it barely pushes on the pressure plate. I could run 2 throwout bearings and it would probably work. Does anyone make an extended throwout bearing with a long nose?

For anyone else doing this - watch your throwout bearing length. Mine needs about a 1-13/16" length. The one I ordered and put it together with was only 1-1/4" and its gotta come back apart again for round #2!

The proper release bearing depends on the style pressure plate. Mine needed the shorter release bearing. My buddy in VA needed the longer version and I was there to help install it. Chevy really only used 2 versions for many years. Also, pull the seal and add grease to the release bearing before installing. These companies use a bare minimum. Mine was growling after only 400 miles of light use.

I agree with the others about staying in close contact with Lugnutz. I did the T5 swap in my 52 3100 5 window. He was a wealth of information and help. Not too sure I would have gotten it right without him. My T5 came from an 88 Sonoma with a mechanical speedo. exactly what I needed. Pulled it apart. everything looked good but rebuilt it anyway. Bolted right up. Love it.

Many thanks to Lugnutz, I took my first drive with the T5 today, and WOW, does it make driving the old truck soooooo much better. There is a gear for every situation and it shifts like a dream.

Excellent!

For anyone following this post, I just got the Jeep 10 spline shaft and all the seals and bearings. I expect to be pulling it apart for the swap pretty soon. I had my clutch inspected before doing this and it was deemed to be in really good shape, so I don't have to change it. Lugnutz has a really good blog that covers the Jeep shaft swap, and I am reading it several times to make sure I am ready to do it. Wish me luck!

Oldie,
I sent you a PM.
Jay

For anyone following this post, I changed out the shaft and shimmed it and followed Lugnutz directions and everything came together well. It is all back in the truck, though I am a long ways from driving it. But that is one major project out of the way. Couldn't have done it without Lugnutz help.