1966 C-10 - Transmission Help - SM420 to T5 swap

I'm pretty sure that the bellhousing on my truck (350 engine w/ sm420 tranny) is broken. I tried tightening up the tranny to engine bolts, but they're already tight. Looking at the video below, you can see how much the transmission is moving around.

tranny from bottom


I was planning on putting in an overdrive transmission eventually, either a 700r4 or a T5. 700r4 seems to be much easier to find around here, but from what I've been told, its a lot of work. I'm thinking that doing it is beyond my abilities right now.

Have any of you put a T5 in one of these trucks? Any tips... anything I need to look out for?

Thanks.

 

Lyndon--

since you can't search for short words on the hamb search, try google
see if any of these threads will help?

btw guys I've been talking to Lyndon off line about this for a little while, I don't know the T5 stuff he needs to know about which trans to get and what it takes to make it fit the SBC if it's from a 2.8 or 4 cyl S-10 .

he's in a bit of a bind, daily driver down, etc....

 

Thanks Jim.

 

I'm planning on putting a T-5 in my '66 as well. I haven't done much research so far, but here's a few links I've saved.

http://www.chevytrucks.org/tech/s10t5.htm

http://www.5speeds.com/t5/index.html

Good luck! I'll be watching this thread to see if anyone else has already done this...

 

to do a t5 you will need a hybrid, camaro case/s10 tail to hold up. you will also need a different disc (fine spline) and I'll bet the driveshaft will need shortened.

 

Thanks for the input everyone.

It looks like I may need to get a bellhousing for the old tranny for now, just so I can get back on the road. My daily is all torn apart right now - trying to get it ready for paint this week, so I need to get back on the road now, or soon after getting back from vacation.

I figured that I'd want a camaro (WC) tranny with the short s-10 tail, but didn't know about needing a different disc. I was also thinking that I'd have to make some modifications to the driveshaft based on the tranny length.

I was thinking about putting one of these behind a 292 and much of the same work needs to be done.

 

What input shaft does the Camaro V8 trans have? is it 10 spline like the old GMs?

 

it is 26 spline iirc.

 

A few days after my last post on this thread, I figured out what the problem with my transmission was - the bolts securing the transmission to the bellhousing were all missing. Squirrel told me what size bolts I needed and after a few minutes I was back on the road.

I've decided to collect the parts that I need now, since I still plan on doing this swap in the future.

One thing that may change how I go about this is that I may be doing an engine swap. I originally planned on using a 292 I have in my 63 nova (my daily). I am starting to think that I may use the truck as my daily driver instead and in the hopes of saving some gas money, may run the 292 in the truck instead and put the 350 from the truck in the nova.

My question is, if I set up a T5 for the truck running the 350 now, am I going to need to do something different if I swap out the 350 for the 292 later? Are the input shafts different?

 

292 and 350 should be directly interchangable.

 

thanks for the help.

will a stock s-10 t-5 hold up with a very mild 350? do the s-10 version and camaro version have different input shafts ( i think i read this somewhere)?

 

How does a NWC T5 compare to a Saginaw in durability.

I know Jerry has done a C-10/T5, or 3.

 

any thoughts on this? anyone else try it?

 

I have put a t-5 in a 65 suburban. Drove it from Phx to Mokan in 06.

I used the stock to the truck bellhousing, a 1 1/8 inch 26 spline clutch disc from a camaro. This was a nwc trans, has held up so far. I think that if it is not abused, 3500 rpm clutch dumps etc it will last as long as a saginaw. I did have a single piece driveshaft made for it. With the longer trans you don't need the center carrier style 2 pc shaft.


jerry

 

which t5 did you use (s-10, camaro)? was this behind a v8 or a L6?

Thanks for the help.

 

Camaro NWC, v-8 car.

I have done the s-10 swap. Just needed to shorten the pilot part of the input shaft and the front bearing cover, about 5/8 inch IIRC.


jerry

 

thanks for the help everyone.

 

i can't believe what this auction went for. this is for just the s-10 parts you need to add to the camaro tranny -

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=140209207981

 

Wow, whole s-10 trans go for around 250 on eBay.

I put an s-10 t-5 from a 89 v-6 in my 70 C-30 w/ factory 350, dual wheels , 4:10 rear. Did this about 5 years ago and have put about 5000 miles on it. I don't beat the shit out of it, just drive it normal. The truck weighs 4000 lbs(flat bed) And I'd been over the scales at the scrap yard at 8000. Mine has the 3.76 first and .72 OD. Maybe it ain't gonna go 100,000 miles, but so far it's fine.

Frank

PS, measure the hole in the bell for the bearing retainer, the truck bell you got is probably too big, and a spacer ring need to be made to shim the hole down to 4.688 (I think 4 11/16)

 

I think I figured out what I'm going to do about the tranny. Found a guy that will sell me a rebuilt WC t5 from a v8 (for about $600) and will add the s-10 tail for another $200. Sounds pricey, but I'm starting to think thats not bad based on the prices I've been seeing.

I've been watching ebay and checking locally -

s-10 tailhousing w/ mech speedo - $200-$300
WC Camaro t5 - $400-$600.



What bellhousing should I use with the T5 camaro/s-10 combo? The SM420 uses a different bellhousing (thanks Squirrel).
Also what about the driveshaft? Squirel said that the SM420 uses a bolt on and not a slip yoke. Should I take the driveshaft that is currently in the truck and have it modified or should I just go to a pick and pull and take one from another truck (I think I know where there's a 67-72 longbed) and have that cut down?


thanks.

 

I ended up getting a 'rebuilt' WC T5 with the s-10 tailhousing attached off of ebay about a month ago. It was more than I wanted to spend, but after checking out prices I thought it was a pretty good deal.

Here are some pics of the tranny - I am a little concerned:

Is this normal (silicone or whatever on outside of case)?


I would have thought this would be cleaner:


Do I need to be concerned about this damage?


Do you guys think I should pull it apart to see what it looks like inside?

I also need to figure out what bellhousing to use and what to do about a driveshaft.

 

I haven't touched this thing for a while. It ran ok for a bit and has started acting up again recently.

I have been getting ready to do this swap, but the guy that I have to help me doesn't really think that the T5 is going to hold up and he has suggested just going with a 350 and swapping out the rear end.


Anyway, I took another look at the tranny when it starting acting up again. I just found this:




I'm told that this is a special bellhousing that is particular to this tranny. Instead of trying to track one down, I plan on doing the swap when I get back from my wedding/honeymoon in Oct. I want to start collecting everything now.

What bellhousing do I need to get?

 

Has anyone used a T-56 in one of these?

 

http://www.cardomain.com/ride/2391572

http://www.ls1c10.com/specs.html

 

What are you hearing about the bellhousing: that the mating surface with the trans is different (the trans won't work with that bellhousing), or the bellhousing from a 6 cylinder won't bolt to a V8?

My '62 283 Suburban came with the 4spd Granny, and it accepted a late model Muncie-style trans mounting surface. Is the mounting pattern on a T5 the same? Not wanting to sound like a total retard, but it's 1:30 in the morning.
Those truck bellhousings (with the cross member mounts) show up all the time at swap meets. They're different than the '55-'57 Chevy bells: one has two bolt holes on each ear, one has only one bolt hole on each ear, but I don't remember which is which (a guy at my swap meet showed me earlier last year).
-Brad

 

Looks like I'm the one that's confused (as usual). I found that old email that I was thinking of:

I thought I was told it had some sort of special bellhousing that was specific to the sm420 and wouldn't work with anything else.

I guess I just need to see if I can get my hands on a bellhousing, get the driveshaft cut, and in theory, I should be good to go?? I think I know where theres a 67-72 longbed at a pick and pull. I think I should go and get that driveshaft and have that cut.

 

The oddball bellhousing was the 60-62 that used the hydraulic clutch.

Your new bellhousing is in a box awaiting your shipping address.

And did you notice the broken trans/bellhousing bolt? top left

 

As soon as I saw the video, my first thought was that the tranny was loose. Good cheap fix though, buys you some time.

I bought a '65 Chevy one-ton panel years back with the SM420 box. The owner said the tranny was shot, I drove it and it did shift hard and had this bind to it. I took it home, crawled under with a few wrenches and within 15 minutes it could be driven and shifted with one finger.

Bob

 

Thanks Jim!

I didn't notice the broken bolt... Is that the shiny spot in the bottom pic(top left corner)?

 

An update...


I ended up selling the c-10 last week. The guy was planning on having the old tranny rebuilt or installing an automatic, so he wasn't interested in the T5.

So now I have the T5. Trying to decide if I'm going to sell it, hold onto it for a later project or put it in the Chevy II. I pulled it out of the box to take a look at it again.

I think I may have a problem. Is it possible I got a ford tranny? I read somewhere that the only number 'that counts' is the one on the tin metal tag on the tailhousing. There is no tag. The other thing is, the tailhousing was swapped for an s-10 one anyway. Here are some pics of the numbers I found on the tranny. On my receipt for the auction, it says the tag is Tag # 1352-176. I don't see this number anywhere. The 065 does come up, but as a ford transmission.