Technical Can't find clutch for 1954 GMC and t5 transmission

I need some help and advice on a problem I have encountered with my 54 GMC half-ton model 100 pickup. The plan was to switch out my granny four speed (enclosed driveline) and original differential with a T5 transmission and 12 bolt Chevy rearend but keep my 270 engine (stock engine was a 248), partly due to cost to replace the engine but to also keep some of my truck’s character.

Here is the problem. The shop has told me THEY HAVE NOT BEEN ABLE TO FIND A CLUTCH that will work with my 270 AND the T5 transmission. After 3 weeks and lots of looking, they have been unable to find any other options. They said at this point I have to consider switching my engine out, suggesting the 350 as a good option.

Here is my question:

Is there anyone on the forum with experience or a solution for a clutch that will work with a 1954 GMC 270 and any T5 transmission?

 

I'm not sure what t5 you are using? If it's a 14 spline input from an s10, then a disc from an astro van will likely work. They are 10.5 ". Use the pressure plate from the 270 provided it covers the disc surface properly. You may also need to grind some of the hub off the disc for it to not be forced into the flywheel with the trans bolted up tight.

 

Have you seen the article over at Stovebolt? https://www.stovebolt.com/techtips/t5tranny.htm

 

IF you would have put your location on your profile page.Maybe some one could recommend a place near you..

 

Thanks wbrw32 for suggesting I put my location on my profile page which I added.

I also read the article from stovebolt.com that was suggested by a couple of members. I'll check with shop doing the build for me to get their ideas. I am still hoping for a better suggestion other than having to piecemeal a clutch package together and grinding down the clutch disc. The quote from stovebolt.com was, "so I used a 11-inch flywheel and an '85 Astro Van 11- inch disc with a pressure plate from a small block. Used a throw out bearing from an SB but for a cast iron fork. Use the stock fork and clutch linkage. This setup put me within about .100 of running out of clutch splines on the input shaft. Enough to dis-engage but barely. I think if I ran out of splines I would have ground down the clutch disc hub a little."

Thanks to the forum members for taking time to respond. I'll continue to watch for any other suggestions.

 

When you piecemeal major components that never belonged together, you need to piecemeal the smaller parts as well. Nothing wrong with a little grinding on the hub for a touch more clearance.

 

Call Fort Wayne Clutch in Fort Wayne Indiana, they can just about solve any clutch problem.

 

If you have the 14 spline input shaft T5, Speedway has the disc listed in the "2017 STREET CATALOG" #515 , page 312, available in 9", 10", & 10-1/2" diameters for $84.99 ea. Hope this helps.

 

They are in the newer catalogs also, good info for you.

 

David,

I needed a 10" Clutch disc to adapt a Camaro 5-spd to my '49 Flathead. All I could find for Chevy splines was a 10-1/2" disc. I called Carolina Clutch and Brake on a Monday and got my new disc on Friday! (I'm in Florida)

I gave them the number of the Chevy main shaft splines, and they custom made one that works perfectly, for $95. They can build you anything you need, brake, or clutch wise. They even relined some Crosley brake shoes for me, years ago!

Don't have their number handy, but you can look 'em up on the Internet.
Their address is: Carolina Clutch and Brake
430 HWY 70E
Hickory, NC 28602

 

If you "DONT WANT TO PIECEMEAL A CLUTCH PACKAGE TOGETHER " just go to your local Walmart and get one of the engineer, brain surgeon, technicians to pull you a 270 engine to T5 transmission clutch kit off of the shelf ....there is NO ROOM FOR PIECEMEAL in HOTRODING

 

Thank you so far for all of the help and advice that has been posted. I did look at the speedway motors catalog on page 312 and was very hopeful that they would have a clutch disc that would work. However, after spending several more hours on the internet and at the shop today I can give you a much better idea of the problem. On the AD Chevrolet pickups the flywheel has a recess in it (for the clutch disk springs) to allow the clutch disk to lie flat against the flywheel. On my GMC 270, the flywheel is flat with protruding bolt heads that mount the flywheel to the crank. Since the flywheel is flat and there are protruding bolt heads, it is the clutch disk that is recessed instead. When you try to mount a flat clutch disc to my flywheel the springs on the disc and the bolt heads on the flywheel prevent the disc from making contact with the flywheel.



So my understanding is that there are no clutch discs like this one that will work with my T5 transmission which is a 93 S-10 26 spline.

 

You could send your clutch disk to ft Wayne clutch and have them rebuild it with the right splined center for the t5 and a new longing on it. Outside of that, I don' know what else you could do...

 

Thanks for the suggestion Nailhead Jason but the shop did talk to me about several clutch builders they have talked to. The shop was told that since the center is recessed like it is, the clutch builders would not be able to build a clutch for me. I'm assuming they just don't have the tooling necessary to build it. It is looking rather bleak at this point.

 

How thick is the flywheel where the bolts go threw to crank?
Is there enough meat to mill a step in flywheel and install a counter sunk Allen bolts flushing the head?

 

Sometimes you need to go beyond what your "shop" says they can do. Have YOU called Fort Wayne Clutch or Carolina Clutch and Brake?

If you are the first guy in the world to ever do this combination, maybe you need to think outside the box. How about adding a 1/4" surface plate to your flywheel, kinda like the bronze inserts on the face of aluminum flywheels? You could run it out past the pressure plate mounting area to space that backwards as well. Just spitballing here.

 

This^

Is there a different flywheel that will work? Stovebolt should have something

 

I have a 4500 series(3 ton¿) gmc flywheel,4 bolt pattern,6v...
It seems thicker than the regular 1/2 ton,do u think u can have that milled?

 

Thanks Alchemy for the suggestion. I have emailed Fort Wayne clutch explaining my dilemma and asking if they would be able to build a clutch disc to fit my application. I'll keep you posted.

 

That's easy, countersink your flywheel for flush bolts then bolt on a disk.

 

Thanks Tman for the suggestion but even if I were to countersink the bolts, the springs on any flat clutch disc will still hit the flywheel. That's not usually a problem in other applications because other flywheels have recesses for the springs allowing the clutch disc to be flat. Here's an image of the flywheel from a Chevy 235 showing the recess in the flywheel which my flywheel doesn't have. I'm also concerned that any milling I do on my flywheel might cause some issues with balance.

 

There is a Very easy Problem Change it to a PowerGlide Aluminum Trans.

and Problem Solved.!

Just my 3.5 cents

Live Learn & Die a Fool

 

People have changed to the Jeep T 5 input shaft that uses the standard 10 spline Used in most GM applications clutch disk. Reading down the page you do have to shorten the end of the input shaft.
In a Chevrolet it makes the unit a bolt in with no clutch mods except for the sleeve on the bearing retainer for the throw out bearing.
https://lugnutz65chevystepside.weeb...ft-swap---diy-and-skip-the-adapter-plate.html
This might be the simple way out if your clutch is ten spline

I bought one of the last Astro van clutch disks that Rock Auto had for my T 5 behind my 8BA but that uses and adapter anyhow In that car I doubt I will ever wear it out.

 

I think my clutch dilemma is solved thanks to Alchemy's suggestion to get in touch with Fort Wayne Clutch in Indiana. I sent them the same pictures I had posted on this forum and the specs for my clutch from my maintenance manual. Fort Wayne said they can redo my clutch with a 26 spline so that it will work with my T5 transmission. The shop who is doing the work on my truck verified that if Fort Wayne can redo the clutch with a 26 spline that will solve my problem. Total cost about $180.00. I'll keep you all posted. Thanks again for all the help and suggestions. What a great group of individuals!

 

I wanted to also thank Nailhead Jason for suggesting that I get in touch with Fort Wayne Clutch.

 

Any updates?
I have a 1950 GMC with the 270 and thinking of the same swap

 

One other key for you guys doing this or any clutch disc problem with a GMC is to use Pontiac flexplate bolts or flywheel bolts for your flywheel bolts. Pioneer has them. They have a shoulder and are a lot thinner than stock to help clear the disc springs. Check the length you may need to ground some off so they do not hit the rear main cap or block. If you have them use the 3 paired bolt keeper plates. They are 1/2"-20 threads per inch.
There are many different lengths of TO bearings usually a diaphragm gets a longer one and the B&B get a shorter one using the stock fork. They are a forging and are great products. The spring retainer for the pivot ball are available.
On mine I use solid discs since there is no street driving.

 

Would a later 235 or 292 flywheel fit the GMC 270? I know zilch about the GMC 270.....