Advice for TH350 Transmission Swap on 62' C10
 

Anyone have any tips or advice on swapping in a TH350 trans into a 1962 C10 long bed? The truck already has a 350 SBC in it from the previous owner, using the front horseshoe style motor mount and bellhousing mount from the 4-speed. Would I need to change to the later style side mounts since I'm swapping the trans and removing the old trans cross member and making a new one? ( Has the x-frame so I think making a new one is probably easier) I'm just worried about getting everything lined up right and also if the motor will have enough mounting points and support. Also, I don't have a lift to drop the old 4 speed trans out, so I was going to just pull the motor and trans together, pop on the new TH350 trans and re-install both. I've been reading as much as I can on the topic but any advice or tips would be great! Anyone have any links or good threads they'd read about this swap? Thanks in advance to everyone.

Re: Advice for TH350 Transmission Swap on 62' C10
 

You have to have at least three mounts total, and the TH350 will only have one mount at the tail, so yes, you'll want to ditch the horseshoe mount at the front and go to side engine mounts. That should be very easy.

Re: Advice for TH350 Transmission Swap on 62' C10
 

Yes you will have to convert to side mount engine mounts. From a quick test fit, the '67-'72 small block rnginr mount brackets seem to fit rather well. Some say a ~1/4" spacer is needed on top of the frame. If this were my truck, I would modify a set of '73-'87 engine mount brackets to fit the early frame. Those engine mounts are a much better design. The original bellhousing crossmember will need to be left out and a trans crossmember fabricated.

Re: Advice for TH350 Transmission Swap on 62' C10
 

You can pull the old 4 speed with a motor hoist by coming thru the passenger side door. Simply pull the shifter, remove the hump, and bolt a short chain to the tranny top cover using the existing bolts. Makes it a one man operation.

Re: Advice for TH350 Transmission Swap on 62' C10
 

Have you made any progress?
Got any pics of the install?
Did you run into any issues?

Re: Advice for TH350 Transmission Swap on 62' C10
 

hello! suggest you use a shor ttail shaft th350, it will be easier to remove if you ever have to service it. you can use the longer tail shaft models but it will stick past the t/bar crossmember you will have to do some twisting and tuning to get it out. that's if you have engine in stock location good luck.

Re: Advice for TH350 Transmission Swap on 62' C10
 

Not a T350 but put a 2004R in my wifes 62.

• Had to remove crossmember. Wasn't sure how much this would weaken the frame so just in case the ends were left on with thoughts of adding support if necessary.
  http://67-72chevytrucks.com/vboard/a...1&d=1402189346
  
• With the cross member and old trany gone there is no side support for the motor, which would make stepping on the gas interesting... so side motor mounts are a necessity. Used 67 to 72 perches with a 1/2” spacers. Positioned the perches with the horseshoe mount and old transmission in place, note; It's actually possible to replace the motor mounts, and transmission for that matter, with the motor in, easier with it out but still possible.
  http://67-72chevytrucks.com/vboard/a...1&d=1402189574
  
• Rear support for the 2004R, quick and easy...but... back to that cut out cross-member my gut feeling when looking at it is that any added HP and/or tendency to stomp on the gas would require more support.
  http://67-72chevytrucks.com/vboard/a...1&d=1402189574
  
• Drive shaft modified to fit.
  
• Transmission oil cooler of course.

Other items I need for the 200-4R:

• New Starter
• New Carburetor for TV Cable linkage, and Intake manifold for the new carburetor.
  http://67-72chevytrucks.com/vboard/a...1&d=1402189574
• Torque converter lock-up wiring and vacuum switch (i.e. 81-82 THM350c) for non computer controlled 2004R and 700R4's.
• Cut hump/Linkage.
  
• Indicator and sending unit. Wanted the Gennie Shifter floor mount indicator/boot because I liked the look and was disappoint to find out that it's no longer available, didn't like the Locar so went with Dakota Digital.

I think that was about it for the trany swap. The truck is still a work in progress, not a frame up just something for my wife to drive around town; clean body with paint, clean interior, power breaks, auto transmission, power steering, 283 rebuilt for reliability, repositioned short person gas pedal etc. probably should have used a 700R4, my thought was that the 2004R might have a less noticeable shift.

Re: Advice for TH350 Transmission Swap on 62' C10
 

Thanks,
That helps a lot.
Fortunately I already installed the same motor perches when I installed a V-8.
My goal right now is to just get an Auto installed for as little cost as possible.
I don't do a lot of highway driving, so the OD wasn't my need.
Lots of Hills and Stop and Go. - Tired of the constant shift up and down of a Manual.

Re: Advice for TH350 Transmission Swap on 62' C10
 

I'm doing the same thing with my 62 but putting in a 5 speed manual, I see the one crossbar has to go but im worried about the crossbar the torsion bars hook to, any thoughts?

Re: Advice for TH350 Transmission Swap on 62' C10
 

Shouldn't be a problem, hard to tell in the above photo but that rear mount for the 2004R bolted to it dead center.

Re: Advice for TH350 Transmission Swap on 62' C10
 

What exactly do you have to do as far as modifying the mounts? Also, this is the first I've heard discussed as far as needing side mounts for a TH350 Trans. I'm confused and nervous at the same time and, wondering if I'm gona be able to pull this off...LOL I remember in a previous thread that I posted about engine mounts you saying that '73 - '87 mounts were in your opinion the best ones to use. I havn't bought any yet in fact, I just got the old motor( 283 with 2 speed powerglide ) out yesterday.

Re: Advice for TH350 Transmission Swap on 62' C10
 

Trucks that came with the manual granny-lo transmission have a single front horseshoe shaped motor mount with side support provided by the transmission mounts, but with the powerglide you already have side support provided by the motor mounts.

Since your mounts are nearly impossible to find those of us starting with a manual transmission and the horseshoe motor mount need to come up with alternatives.

Link with photos

Re: Advice for TH350 Transmission Swap on 62' C10
 

Welcome to the forum. Perhaps the following thread will help. I shows installing a 350/350 in a 1960 GMC:

http://67-72chevytrucks.com/vboard/s...light=sbc+1960

Re: Advice for TH350 Transmission Swap on 62' C10
 

Since you already had a 283/PG in your truck, you will already have the side engine mounts. You're good to go.

Re: Advice for TH350 Transmission Swap on 62' C10
 

I guess I was thinking you meant side mounts for the trans. So, everything mouts at three places, the two side mounts for the motor and, one at the back of the trans?

Re: Advice for TH350 Transmission Swap on 62' C10
 

Yes

Re: Advice for TH350 Transmission Swap on 62' C10
 

I had never seen the 'Horseshoe' engine mount thingy.
My 62 donor didn't have one. Mine was a V6 so it had two lower side mounts fabbed as part of the frame.
Here is a pic I found of the Horseshoe engine mount.
http://i1135.photobucket.com/albums/...z/_DSC3640.jpg

Re: Advice for TH350 Transmission Swap on 62' C10
 

Thanks Mike, I thought that was correct but, with all the discussion with side mounts, I wanted to be sure.

Re: Advice for TH350 Transmission Swap on 62' C10
 

My 62 had the front mount at first but I went up to the later side mounts and fabbed something up for the tail shaft using the old bell cross member and some plate I found in the garage.

I think years ago on my last build I made the old torsion bar cross member work too (after flipping the front clip up to coils).

rg

Re: Advice for TH350 Transmission Swap on 62' C10
 

http://67-72chevytrucks.com/vboard/a...1&d=1402189318
.
Are you saying you just mounted your auto tranny to the torsion bar crossmember?

Re: Advice for TH350 Transmission Swap on 62' C10
 

Yes, motor in front crossmember in back, which is why the motor needed the side mounts.

Re: Advice for TH350 Transmission Swap on 62' C10
 

I understand the front mounting.
My question was pertaining to the auto mount.
I ask because most have to install an auto crossmember. But it appears you didn't. Because you just used the torsionbar crossmember.
I guess I'll have to see where my tranny tail lands.

Re: Advice for TH350 Transmission Swap on 62' C10
 

Attachment 1333857Simple to make in place...I used some steel bar and some angles for mine

Re: Advice for TH350 Transmission Swap on 62' C10
 

Wow, looks nice under there!

Yea a TH350 is approx. 20 3/8 inches from front to rear mounting bolts, 6 5/8 inches shorter than the 2004R.

This link might help.
http://www.tciauto.com/tc/trans-dim

Re: Advice for TH350 Transmission Swap on 62' C10
 

That's a good link...I have 700r4 also and kept my options open with the additional length. The 200r will pose some serious interference with the torsion crossmember.

Re: Advice for TH350 Transmission Swap on 62' C10
 

I vaguely remember seeing a 62 with a 700R4, had a custom tube cross member with a backward bend so that it attached just about where your TH350's cross member is bolted, the R4's tail-shaft housing did extend over the torsion bar cross member but if I'm remembering right there seemed to be room with no apparent modification.

Re: Advice for TH350 Transmission Swap on 62' C10
 

I'm searching the forums looking for how the linkage was installed on the X-Frame.
I'll probably just modify (shorten) the left bracket.
http://67-72chevytrucks.com/vboard/a...1&d=1341419624

Re: Advice for TH350 Transmission Swap on 62' C10
 

Anyone have pics of the linkage there in that pic above mounted to a 60-62?

Re: Advice for TH350 Transmission Swap on 62' C10
 

My 60 has a 700r4 trans.. I just purchased a universal tube trans mount and cut, fabbed, and welded together...then I bolted it to the side of the frame rails.. the universal tubed mounts all look the same but diff application for trans.. There was no issues on fit and was able to use the stock e brake system..Also did the same concept for motor mounts for my 283..

Re: Advice for TH350 Transmission Swap on 62' C10
 

Pretty sure there wasn't anything like whats in your picture. My 63 factory automatic truck just has a rod from the column to the side of the trans . Ive got a 62 automatic GMC I can check but pretty sure its just a rod also.

Re: Advice for TH350 Transmission Swap on 62' C10
 

I'm pretty sure that what is shown in this photo is the linkage for a 67-72 truck with a TH350. I've done a lot of searching on this topic, and several have stated that the 67-72 linkage adapts easily to a 64-66.

Re: Advice for TH350 Transmission Swap on 62' C10
 

Okay, thanks.

I had bought 67-72 linkage sometime back.
I guess I never really researched how the linkage was setup for the 60-62 's.
I'll modify the 67-72 linkage I have to work with my 62 frame.
http://i1106.photobucket.com/albums/...psgohjuyqt.jpg
http://i1106.photobucket.com/albums/...pssqj1ophe.jpg

Re: Advice for TH350 Transmission Swap on 62' C10
 

Here's what I ended up doing.
.
http://i1106.photobucket.com/albums/...psuf3wwg59.jpg
.
Didn't use this.
.
http://i1106.photobucket.com/albums/...psdvnd7swc.jpg

Re: Advice for TH350 Transmission Swap on 62' C10
 

That should work! Looks good.

Re: Advice for TH350 Transmission Swap on 62' C10
 

Thanks.
It's hardened #8 Bolt.
There's not the slightest flex.

Re: Advice for TH350 Transmission Swap on 62' C10
 

Did you have to bend the seam at the firewall to prevent the bellhousing from hitting?
Also I am using the stock 66c10 6cyl engine mounts up front with a 327 and made the rear x-member, but the back of the trans hits the floorboard. I can lower it down in the back, but my engine won't be sitting level because of the mounts up front.
when I made the x-member I made it so the trans tailshaft would be about 3 degrees. If I lower it down the angle will be higher.
Is the engine supposed to be dragging its butt or level?
Seems like I need a high hump tunnel, but from everything I read people say it doesn't need a high hump for th350

Re: Advice for TH350 Transmission Swap on 62' C10
 

Maybe your engine is too far back.
Mine has plenty of clearance with the small hump.

Re: Advice for TH350 Transmission Swap on 62' C10
 

how do I know if its too far back, the distributor has plenty of room and the front eng. mounts are centered in stock holes?
How much clearance do you have between the firewall seam(firewall to floor seam) and your th350 bell housing?

Others said for a 700r4 you need to beat the seam away to get clearance, but not sure if you have to do the same for a th350.
I can beat the seam no problem, just can't understand why the aft part of the trans is hitting the floor also. my aft trans rubber mount base is sitting 3" up from bottom of frame rail on x-member.

Re: Advice for TH350 Transmission Swap on 62' C10
 

I'll see if I can get some pics.
Also look at my build thread:
http://67-72chevytrucks.com/vboard/s...426650&page=20

Re: Advice for TH350 Transmission Swap on 62' C10
 

If you installed the 6 cyl (which are the same as the V8 mounts) in the forward position, that is part of the issue. Your engine is sitting too high. Those engine mount brackets are designed to be installed in the rear location.