The Stovebolt Site Forums The Shop Area Driveline SBC T5 in a 47?

Hi Folks, Finally got my 47 GMC home. Woohoo. Now the work/fun begins in earnest. I'm puttin in a stock 350 currently sitting on a stand ready to go, and a freshly scored T5 out of a 92 S-10. I've read everything I could find, especially from Lugnutz, and that seems to be the combo. Since I'm starting from scratch, I have options on the best way to go from here. Kinda feels like having a kid. You know exactly what you're gonna do until it gets home, then all bets are off. Basically I have no idea from here. I don't have a clutch/bellhousing etc. I really want to keep the stock pedals! I'm also not planning on changing the suspension or steering geometry, but am open to ideas.

So here's my questions:
Should I go with a mechanical or hydraulic clutch? I have no components for either besides the pedal and what holds it to the frame. Does someone make a kit for a hydraulic clutch for the AD trucks?
What is this "adapter plate" that I've read about? I really dread the idea of changing the input shaft of the trans. I pretty much know I'll drop transmission parts all over the floor and accidentally kick them to parts unknown.
Is there a range of bellhousings I can use with said adapter plate? (I need to get all these things and a 14 spline clutch assembly)
My first plan was actually to go thru the entire brake system replacing all the lines etc. and adding in a dual master cylinder in stock location. Can I go ahead with this or will I run into fitment problems that force me to "hang" pedals?
What myriad of other things have I not yet considered?

Just Mark,
The 350 engine should work well with a cast iron bell housing. I have several that keep accumulating in my shop. The clutch fork opening is on the driver's side.
I have been happy with the mechanical clutch linkage in my 1965. I have no idea how easy your frame mounted clutch linkage will work with the 350 and bell.

Unless your T5 has seen low mileage and tender care, I highly recommend that you open it up and clean it. Then change the input shaft to a 10 spline Jeep shaft with a new input shaft bearing. Then get the end play set to zero. I am self taught and did not find my first attempt to be difficult. YOU CAN DO IT. Especially since I can help every step of the way.

The cost of an adapter plate plus the 14 spline clutch package will cost almost 3 times the cost of a Jeep input shaft swap. That's just my vote.

As for the braking system, I'll bet 52Carl knows the answers. I think he's done this once with a T5.

Jay

Thanks Jay. I'm considering the jeep input shaft. I did read through your complete description of the process. Sometimes these projects are overly intimidating at first, but aren't so bad once you're into it. It still seems overly intimidating at this point. Are you interested in parting with one of those bell housings? The internals of a transmission are a world of mystery to me. When you say "clean it", I'm picturing opening a side cover (which this doesn't seem to have) and spray some brakeclean type of chemical, button it back up and hope for the best. I'm assuming you have a better process for that?

Looks like this one? I think it's correct:
https://www.ebay.com/itm/Jeep-T5-In...line-21-Teeth-1351-085-008-/181789554307

That is the correct Jeep shaft. That vendor includes the bearing and race, so less hassle for you.
It’s very easy to open, clean and inspect a T5. You will need some basic tools like socket wrenches, ball pien hammer, a drift for the roll pin and brake clean and some rags. Sealing it up is pretty easy but an extra set of hands is a plus. I can make a short video if you want.
When you open to clean and inspect is the PERFECT time to do the shaft swap. Your 1992 T5 should be non-world class.

Well, looks like you have another T5 apprentice on your hands. I ordered the shaft and bearing kit. If the parts come in by Tues am, I'll do it Tues.
(Leaving for Hershey Wed am)

Do I need a new gasket for the trans cover?

Supply list:
Permatex Ultra Black RTV
Green Scotch Pad
Bearing grease or Vaseline
Clean rags
Brake Cleaner
Wire brush
Socket set with extensions with 10mm, 13mm and 15mm sockets.
A drift and hammer to drive out a roll pin.
A shop press to install the new bearing onto the Jeep input shaft. If you don't have one, I bet your local transmission shop will do it for you.

New seals for the tail housing and input shaft bearing retainer are a good idea.
The shims you will find next to the front bearing race (inside the input shaft bearing retainer) will likely be all you need - just reuse them.

Here's a link to my DIY rebuild of a T5. You will not tear down the main gear train, or remove the countershaft. So don't get overwhelmed. The reverse/5th gear shifter fork will probably not need to be removed either.

I've sent you my email so we can share pictures to help with details.

Awesome. I'm actually looking forward to this! (I still reserve the right to dump transmission doodads on the floor and accidentally kick some to parts unknown)

That’s ok. I have several boxes of extra parts.

where abouts in mi are you im in sears about 35 miles north of mt pleasnt

i have a 51 3100 that i have already changed to a T5 and the new dual resivor master cylnder the hard part is starting

I'm near Durand. About 15 miles west of Flint. The 350 I scored for this project came from a guy in Coleman. Not all that far from you I think.

Well I got most of the stuff together today. Spent some time cleaning up some of the grunge on the outside. I'm still waiting on a seal. I'll move this stuff into my shop for the actual work. That way it'll be easier to find the parts I drop and scatter to parts unknown. I've got real work to do tomorrow so I'm thinking I'll tackle this project Monday morning...providing I haven't chickened out.

Nice work table. Has a slot cut out for the “fin” at the bottom of the tail housing. I have a B&D workmate that works great and allows me to work from either side.
Do you have a new seal for inside the bearing retainer?

I used your ideas for the table Jay. Thanks for that. I'm waiting on that seal. Should be in tomorrow.

I do have a linkage question for anyone with some insight. My truck has no Z-bar or clutch linkage. On my list for Hershey next week is the Z-bar and necessary linkage components. I was specifically going to look for linkage for an AD truck, but now I'm kinda thinking any Z-bar that's basically the right length from the frame to the bell housing. Unfortunately I can't measure that since my trans assembly isn't in the truck. To add to that, I'm not really sure what it's supposed to look like, and not sure the frame part it's supposed to attach to is still in the truck. Anyone have advice on this? Or, are there some decent AD truck pics of this linkage area?

dont realy use a z bar the clutch and brake pedel are on a common support from there there is two pieces of linkage to the throw out bearing arm that comes out of the bell housing realy a simple operation when you step on the clutch pedal it pulls on the linkage rather than pushing these parts are readly avable thru a half dozen realtailers yes and been in your part of the state many times before retiring i lived and worked in the flint aerea let me see if i cant dig up a picther of the linkage take care and ill look for that linkage

A pic would be awesome. Thanks. If you know of anyone specific that sells em let me know that too.

L M C truck sells them brothers sells them ithink if you google parts for 47 gmc truck you will find all the good stuff you didnt know you wanted my repare manual has some picts but they just dont duplicate or copy well i will keep looking for pictures

Thanks. Ordered the parts from LMC. $40 with shipping. Doesn't get better than that. There was an AD truck at Hershey for sale that didn't have a front clip on it. I was able to get a good look at all the mechanical clutch parts. I also picked up a shop manual.

After encouragement and support from Jay, I opened up the T5, cleaned it out and swapped the input shaft. When I pulled off the tail housing a small ball bearing fell on the floor. I literally laughed out loud. I did manage to not kick it to parts unknown. The trans is back together and all the parts are accounted for. I'm very confident that there's an 80% chance that it's 65% correct. It should work.

Thanks to Jay for the coaching and talking me off the ledge so to speak.

Assembled trans and the motor as it sits (not finished)

What color drive gear does your T5 have? I left that part out of my videos.

Uhhh.....Where would I find that? If it's on the inside I don't know.

Remove the driven gear and housing from the tail housing. Look at the drive gear through that hole. It will be either dark red or blue.

More info LINK HERE

did you order the return spring i know i didnt the first time

what about the color what does the color to do must be gear rato for speedo

Dang! Nope.

I'll look at the Speedo gear tomorrow morning.

Need some clutch fork advice:

I'm attempting to use the original AD type clutch linkage and a "621" bellhousing mated to a small block. Will an original AD type fork work with the 70s era bellhousing, or do I need to adapt a fork to match the housing? I don't currently have a clutch fork and need to order one, but there seems to be a million of em.

So I got the motor and trans assembled together. Everything fit like it was supposed to. Strange, that never happens. Planning on putting it in the truck thanksgiving weekend at a buddy's shop in Warren Mi. I bought the Chassis Engineering mounts. They're really nice quality parts. I'm anticipating it to be a big project though. Wish me luck! (yes I know there's a bolt missing, it'll be in soon. lol)

I was considering doing a proper build log on this truck since it's a pretty big project on an aggressive time schedule, but John seems to have a pretty tight requirements (understandably), and this really is just another 1/2 ton Ad, and to top things off it's actually not a stovebolt. Although the original plan was to put a 292 in it. It just didn't fit. ( I do know someone with a pretty sweet 292 available though, lol)

Also got the brakes done. Was planning on sticking with drum brakes, but to many parts were missing and this is a 47 with "Huck" style brakes and parts were becoming difficult to find. I'm glad I went with the disks now though. Thanks to the guys at Dave's Muffler in Durand. They did all the work on the brakes. (I have no affiliation with Dave's Muffler other than being a long term satisfied customer).

Made major progress over the weekend. Got my motor and trans mounted in place. That S10 T5 puts the shifter exactly in the sweet spot.
I did run into major clearance problems with the steering box. As somewhat expected. Been reading a bit on solutions, but haven't gotten it figured out. ANY advice would be appreciated.

Power steering would solve your exhaust clearance issue. Then you can use rams horn manifolds. You will need 2 which exit straight down.
Power steering is an awesome upgrade too.
I can't tell from you pic if you have room for the 265 engine manifolds or not. Looks pretty tight.
Some have rigged bracketry to allow the steering box to the left for more clearance. I don't like that option personally.
Carl

Just Mark,
You would really enjoy a short throw shifter. Not that difficult to convert your current shifter to short throw. It's in the TECH TIPS section HERE.

Carl, Thanks! I'm just starting to dig into the power steering idea. I'm hoping to find the magic combo of inexpensive, high quality and easy to install. Or at least inexpensive. Lol

Jay, Thanks. I gotta do that! I'll post updates when I get to that project.

Sometimes things are just to cool to not take time off work to do...and take a good money job out of the CNC to make up a spacer.
I'll reassemble this thing after the Hurst shifter is welded in place.

OK, so I just read the "don't post images in the forums" thing. Sorry about that! I'll learn how to do the "link" thing.

Mark, you are just fine posting images as you did above. We have changed things up a bit and you may have read some older info. All is good.

Oh cool, thanks.

TADA!

Take a bow! Looks very nice.