Anyone run an SM-420 Trans.

[Dads64]

Just trying to figure out what I am going to do Trans wise. I currently have the SM-420 that was mated to the 350 but I want this truck to be a 450-500 HP driver and don't think this trans is the way to go. I am kinda wanting a standard but am on a budget too.

Also, will the stock trans crossmember work with any other trans?

Thanks,
Jay

[rcbildr]

For many years my 63 ran with the SM-420 that's in it. It was behind a 283, then a nice 383 til a main bearing got spun, and then a 307. I'm going to swap in an SM-465 because it's set up for 4x4 and I know the 420 has close to a million miles on it. If your trans shifts fine, I think it would be ok to run until you can get what you want in there.

[blackedoutharley]

The SM420 is virtually bullet proof so long as you realize its not a racing transmission. I refuse to change mine out.

[1972RedNeck]

We have several around the ranch. IMO, they shift much better than the 465. They also have a lower first. The only transmission I would change them out for is a NV4500 and only because of the overdrive.

[Dads64]

I may have to run this tranmission for a bit but last night I found possibly a bigger issue. I was going to take the trans crossmember out for frame prep and have now noticed that the pivot arm or what ever you want to call it for the clutch, which I guess is normally mounted to a beacket on the frame and then to the engine with pivot bolts, has had the brackets welded to the crossmember and the frame. The shaft that has two arms on it was all messed up and didn't pivot correctly so it needed to be taken out. The only way to do that was cut it out. I could be in trouble here LOL.

I will take some pics of this this evening on the truck I am building and the other stock '64 I have for parts to show what I am talking about. I am guessing it was changed when the 350 was put in.

Just a bunch of newb issues I am sure, I am lucky to have this site that is for sure!

Jay

[Dads64]

This is what I am talking about and how it looks on the stock '64 with the straight six.



And here is what someone welded in and set up in the '64 I am building. I had to cut it out.

[blackedoutharley]

Maybe I'm missing something here but why not just go with the original linkage set up using the factory tab on the frame rail?

[Dads64]

Agreed, I was just taken back when I saw how it had been all moved around and what not on my truck. When I had to cut it out it got me to looking and that is what even made me notice it was wrong so to speak. My parts truck will come in handy in replacing all of it.

Jay

[1964c-10]

that may have been done to clear headers

[Dads64]

If it was the header were gone before my father got the truck as it has manifolds now. I never paid any attention to it before having the truck tore all the way down. I am just going to cut it all out of there and clean it up. I have the full setup on the other truck so I can put it back the way I feel it should be based on my build. Sure am glad now that I picked up the other truck.

Jay

[Captainfab]

I see no need to remove the bellhousing crossmember. All that needs to be cut off, is the bracket on the crossmember, and the one on the bottom of the frame. But that of course is up to you.