Another sm465 question

[BrianCarroll]

Ok brand new to this forum but have read many posts. Be patient with me.
1979 c-10 SPORT (which is rare) and 2 wheel drive 5.3 LS SWAP
I have a sm 465 but is leaking gear lube at front of trans I dont know if it is in the bell housing yet I suspect the front bearing and seal. Although there are no bearing symptoms.
What I want to avoid is ruining the new clutch that just went in a few thousand miles bac.
I always understood sm 465 were all the same now I found there were at least two types, up to 1972 there was a mount on the bell housing.
73 and up had a rear crossmember mount at the end of the trans.
This is the transmission I have.

When I noticed the leak I ran out and bought a beautiful sm 465 300.00 with a clutch and disk.
I thought that was a good deal however yesterday pondering how I was going to remove and replace that 175 lb monster
I observed there were no rear mount on my replacement transmission.(old style)
But looking at the rear part of the trans it looks like i could swap the casting on the end of the trans thus assembling the old style sm465 with the bolt on rear from the new style .
So I guess my question is can I convert the transmission to a new style by swaping out the casting by putting the tew stylre back end with the trans mount in the casting on to the old style transmission.
Is this feasible to do or is it complicated.
I would love to hear comments on this subject.

If this is already covered in detail please direct me to the post

 

[BrianCarroll]

OK SO IT APPEARS NO ONE ON THIS FORUM KNOWS IF i CAN CONVERT A EARLY SM465 TO A LATER MODEL WITH THE REAR MOUNT BY CHANGING OUT THE REAR HOUSING .

wow

 

[Catbox]

Damn man.
Calm down.
I never even saw you post the first time around.

You are sure to get a better answer by simply asking for help again rather than using your upper case voice in here.

But also, perhaps nobody has done it so you are the guinea pig to do the test.
Oh and I have no idea if it will work.
My SM465 just leaks and I keep filling it.

 

[Bextreme04]

OK SO IT APPEARS NO ONE ON THIS FORUM KNOWS IF i CAN CONVERT A EARLY SM465 TO A LATER MODEL WITH THE REAR MOUNT BY CHANGING OUT THE REAR HOUSING .

wow

I agree, I never saw the initial post pop up... it must be a forum thing. I'm not SM465 expert, but I don't think there is a split at 73 for different models of SM 465. My understanding of early and late is that the early SM465 is from 1968-87 and the late is from 1988-91. What you are asking about is just a different tailhousing/adapter. As long as the tailshaft is the same between the two transmissions, it should just bolt right on and work the same as the other one. If the tailshaft is different, you would need to swap that over as well(which you should be able to do.. since they are essentially the same transmission).

 

[dvdswan]

Welcome to the site. Try checking the NOVAK site. They might have the information you need.

 

[BrianCarroll]

oK GUYS HERE IS THE ANSWER TO MY QUESTION RIGHT FROM WEST COAST STANDARDS A SHOP IN CALIF.

There is a difference in the two transmissions 1st version has rear mounting on the bell housing
that goes from whatever year up to 1972. That was the end of the bell housing mounts.

1973 has the rear mount on the very back end of the transmission casting so they will not interchange.
However here is the response from Brian Turner at West Coast Standards 866-571-4327

"yes you can change the tail"

He is referring to the rear end of the transmission about .75 inches thick casting. 7 bolts it houses the speedo connection and rear bearing
If you look closely you will see that the only difference between the old style and the 1973-1987 (not sure about the year) is the 73 and up have two ears on the back end of the casting for the bolts for the crossmember .

So to summarize you can make an old style fit to a new style truck or go the other way .
It happened in my case I bought the old style transmission that i later found had no mounts for the crossmember.

Now I can switch out the rear casting with the 7 screws and acts also as the rear bearing housing.
I am only doing that as my new style has a leak and the old one is still as new it a beauty.

Beware the new style after 87 has the aluminum top and shift lever is positioned about 4 inches farther back which would require a new shifter hole and carpet.

Ok so I answered my own question and I posted this for people to access the answer and thanks to West Coast Standards for providing the answer to me.

 

[PrairieDrifter]

I could have told you that. Didn't see the post either.

The transmissions are the same, the earlier ones just don't have the mounting foot on the rear of the trans to bolt to a crossmember, because thats not how they mounted. This style of bellhousing was offered all the way through 87 or 91, whenever they stopped making the c50 and heavier trucks. Partly because some trucks utilize an emergency brake mounted on the output yoke of the transmission. Also may be stronger?

So really, the bellhousings and the back plate are the only thing different.

 

[Bextreme04]

I thought I did tell him that... yesterday

 

[BrianCarroll]

Ok Men I did not mean to blow up with all the upper case stuff.
I will try to be a better member.
My truck 1979 SPORT Truck Scottsdale fleet side LS Swaped I dont know why I am messing around with the sm465 I should be looking at a 4L60e to put in .
Finally gave up on the wiring is is in the shop now getting a few issues resolved.
My primary issue is that when you turn no the headlights with the key off the fuel pump starts to run.
I think the guy that put in the american autowire harness got some wires crossed.

 

[Bextreme04]

Ok Men I did not mean to blow up with all the upper case stuff.
I will try to be a better member.
My truck 1979 SPORT Truck Scottsdale fleet side LS Swaped I dont know why I am messing around with the sm465 I should be looking at a 4L60e to put in .
Finally gave up on the wiring is is in the shop now getting a few issues resolved.
My primary issue is that when you turn no the headlights with the key off the fuel pump starts to run.
I think the guy that put in the american autowire harness got some wires crossed.

Sounds like the guy that did the job definitely messed up a few things. I wouldn't mess with a 4L60 unless it came with the engine already. Otherwise you might as well just drop in a junkyard 4L80 and send it. Especially if you ever plan on adding any power to the LS.