QUESTION: 3-speed and 4-speed SAGINAW mounting???

Are 3 and 4 speed Saginaws directly interchangable? Meaning can I just unbolt my 3 and bolt on a 4? I'm not concerned with the shift junk yet, just bolting it to the bellhousing and making it work. Thanks!

 

You could measure them, but I'm sure that they are the same length.

 

I'm also not concerned with the length, just the mounting of it to the bellhousing. There is no driveshaft yet. I don't have the 4-speed to measure, I just found one for sale that's a good deal.

 

if it helps, a 4 speed saggy and an aluminum powerglide interchange. only modification was to "C" notch my crossmember to clear this inch wide boss on the bottom of my 4 speed's tail shaft housing.

 

They should be.

Josh

 

Kirk- it will bolt up if your bellhousing is a 54 or newer and is from a passenger car....some trucks have a larger input shft COVER diameter.....4 spd should be same 21-3/4"length as a long 3 speed is....

 

yup...watch the front bearing retainer, but they should interchange if you need to swap them.

 

To answeer your question very simply, YES. I have a 70 Chevy PU. Has a T5 5 speed now came new with a saginaw 3 sp. has had a saginaw 4sp and a muncie 4 sp. Chevy is not ford most things interchange.

 

What do you mean? I am manual transmission retarded.

 

Some chevy trucks and i mean trucks came with a different bellhousing nothing to realy worry about. If you need them i have both a 3 and a 4 speed saginaw for sale.

 

The big round hole in the bellhousing, where the front of the transmission fits in, is bigger on most 68 and newer Chevy trucks, because those big 4 speed granny gear trannys that they use needed a bigger bearing retainer. To make life simple(!), they also made the bearing retainers on the 3 speed trannys bigger to fit the newer bellhousings with the bigger center hole.

Just make sure the tranny fits into the bellhousing properly, if there is play between the front round part of the trans and the hole in the bellhousing, it might not stay in high gear. If the hole is too small, the tranny wont' go in all the way.

On the Saginaw 3 and 4 speed you can swap the front bearing retainer to get the one that matches your bellhousing.

 

The saginaw 3 and 4 speeds have the same bearing retainer unless your talking about a 4 sp granny low tranny from a 1 ton or bigger truck.

 

I have a 3 speed saginaw laying in front of my shop...from a 69 chevy pickup...it has the bigger truck size front bearing retainer on it.

I can take a pic of it tomorrow if you'd like.

or you can look up GM part number 3859032 and 3920738 if you want.

One is for car 3 speed saginaws and trucks thru 67, and the other is for truck 3 speed saginaws 68 and later.

 

I have 2 70 chevy pu 3 sp trannys in my shop and a 83 chevelle 4 sp and i will take pics of all three retainers all the same

 

two part numbers does not mean two different sizes

 

I may be into the 4-speed if this deal falls through.

 

They list the od of the small one, but not the big one.

Have you ever seen the 5 bolt mount Saginaw trans in a 73-up pickup? measure the bearing retainer on it.

 

Your talking about two different things. Have never measured a 5 bolt retainer, they are not common. All 4 bolt saginaw tranny i have ever changed(for the last 30 years and that is a lot) have been the same size. I have a 53 Jeap with a early chevy pu bell housing and a granny low saginaw tranny. The bell housing came out of a three speed pu. My 60 IH scput has the same type bellhousing (motor mounts on it) with an early saginaw 3 speed (Floor shift on the tail shaft) all bearing retainers are the same size. I believe those 5 bolt trannys are from 1 ton and bigger pu's

 

whatever you say dude, you're the expert.

 

What ever dude take real pictures so we can see the whole thing not just what you want us to see

 

What do you want to see? should I get the mic out or what?

that Saginaw bearing retainer is indeed the same size as that truck bell, and the hole in the 621 bell is indeed quite a bit smaller.

Really, I'm not bullshitting you, there are Saginaw 3 speeds with the big truck size bearing retainer on them. Honest!

 

They ARE FUCKING DIFFERENT!!! Period. The trannys that have either 5 bolts or the 4 bolts that have threaded lower bolts, have the larger bearing retainer. I have one of each.

 

here are 3 more pics...but I suppose this won't prove anything either.

The trans is out of a friend's 69 chevy half ton pickup, it was stock original when he took it apart 15 years ago.

oh well.

 

Here's a pic of my 4 bolt truck tranny bearing retainer being turned down to fit the normal car one.



Tranny looks practically identical to the non-truck ones...

 

thanks, I thought I was losing my mind or something.

I gotta get me one of them turret tool holder thingys

 

Nope 69 chevy pu had motor mounts on the bell housing that one do not quess again

 

Also had dust covers until much later

 

The transmission is from a 69 truck, that bell is obviously from a 73-up truck...I have a 68 truck bell with the big hole in it I can put on there to take pics, but you'd claim it was the small hole version, that's why I put the later bell on the Saginaw. Now you KNOW the saginaw has the TRUCK size bearing retainer on it.

Come on, you can admit that you learned something today, can't you? I learn shit all the time on the hamb, and I though I knew a lot before I came here. I was wrong.

 

So what did i learn, the trans from a 69 pu will fit a later bell housing Knew that proves my point the will interchange

 

Guess i have never found the small one