3 speed saginaw replacement with 5 speed

[mikeoverland]

Hello all,

It has been a hot minute since i've been online asking anything but my personal life and family life are currently in shambles. With that said, I have been thinking of replacing my 3 speed saginaw with a 5 speed out of a s10 or s15 with a 4.3. Has anyone ever tried this before or is this a swap that only happens in books. I was thinking that with a 5 speed I would have better cruising (real lower rpm) while driving on the freeway. I'm thinking that the transmission would be a bolt in but I'm guessing at this point. Ive got it figured that *IF* it could be done, someone on this list has done it so I'm trolling for information, advice or a good shrink to tell me that I'm way off base.

Thanks a bunch

Mike Overland
Leon Springs Tx
owner of the insured but not tagged yet 1981 C10 known as "the basket case"

 

[Frankenchevy]

Are you referring to an nv3500? I think someone here has one, @bluex maybe?

Anyway, I believe that’s a hydraulic TO and your truck is mechanical clutch linkage. If so, you’d need to sort that out.

I went with an Advance Adapters bellhousing and clutch components from a newer square to get the hydraulic pedal, etc. when I installed an nv4500. I believe 86 and up are factory hydraulic setups.

 

[Ricko1966]

An np833 would get you a 3.06 1st and a .73 4th it's not a 5 speed ,but it would be an option to get you overdrive.

 

[bluex]

I did the nv3500, not all of them are internal slave but they all are setup for hydraulic operation. It was basically a bolt up. Further details are here:

NV3500 swap

This is how I went about installing a 96/97 S10 NV3500 into my C10, this way worked for me and will probably be a little different if you use an older or newer transmission. I would stick with 96 and up though as they are the strongest versions of them. Parts list: Purchased through Rock...

www.gmsquarebody.com

 

[Strick]

Years back I put a 5 speed from an S truck into my dad's crew. The input was like 28 spline and the largest diameter clutch that I could get was about 9 1/2. The first couple gears were alright but the clutch would slip easily in the higher gears. I pulled it and put the SM465 back into the truck. I would definitely investigate the clutch diameter before doing the swap.

Strickland

 

[DoubleDingo]

Check out Stovebolt, there is a member over that did it. Of course his truck has an old inline 6, and the 5 speed keeps the rpms in a good range, so you can expect better driving manners on yours if you do the swap

 

[mikeoverland]

and this is the reason that i love this list! if it is possible, someone has done it before!!!!!!!!! thanks for the info and the advice. now to find a transmission...

Mike Overland
Leon Springs Tx
owner of the soon to be legal to run on the streets 1981 C10 known as "The Basket Case"

 

[410 John]

Are you going forward with this swap? I’m considering the S10 T5. Mine C10 has the truck 4 speed. And there’s a 5 speed for sale locally. I’m just hesitant to pull the trigger.
Also, I’m pretty sure a 4.3 S10 would be 10 spline and the finer spline would be a 4 cylinder or 2.8.

 

[410 John]

I was wrong on the spline counts and applications. There’s no 10 spline T5. There’s is a 14, though.
Good info here:

Thinking about installing a T5? READ THIS FIRST

This page is for someone CONSIDERING installing a T5 transmission. Will a T5 work well with your Chevy engine and bell housing? Yes, probably. Here's a list of things to think about. ...

lugnutz65chevystepside.weebly.com

 

[Elliot W]

I recently did the nv3500 swap. What I wish I knew before starting is that not all nv3500s are the same aside from the 2wd/4x4 aspect. The transmissions are different lengths depending on if you got it from an s10 or sierra/silverado. And the shifter is a couple inches further back from the bellhousing on the s10 too. Also the shifter assembly is different between the two and cannot be interchanged. If you do get it from an s10, it has to be from a 4.3 motor. Hopefully you can find one...it took a while for me to find one that would work. I ended up going hydraulic clutch which wasn't as bad as I thought it would be.

 

[squaredeal91]

Me and a friend swapped in a 4.3 5 speed from an s-10 into a wrangler with a small block and a random truck flywheel and clutch. I believe it was an 11 inch flywheel. Slave was external and for being a v6 Trans was very happy with the results.

 

[410 John]

NV3500’s still have clunky shifting? Am I correct?

 

[squaredeal91]

NV3500’s still have clunky shifting? Am I correct?

The ones I've driven shift nice

 

[Elliot W]

Mine shift just fine. I wouldn't race with it but for getting the 5th gear without paying for a t56 I'd say it shifts plenty nice. Mine is from a Sierra so it shifts like a truck.

 

[CalSgt]

I did a Getrag 5 speed in my K10 in the late 90’s. Fairly simple swap.

Did a hackjob hydraulic clutch master from a GMT400. And had to source a different input for my 208 transfer case, actually just bought a 208 that had the correct input out of the BigNickel classifieds.

Dad sourced the trans for me so I’m not sure what it came out of or the part number. I swapped for a 700R4 a few years later, the 5 speed is in the shed. I’ll see what model it is.