sm420 in the flattie

well if i mess with the tranny, i'll go to thechev 4 spd. thanks though.

 

I have SM-420 swap with Dana 20. Where can I get a speedometer cable long enough to run from the transfer case to my speedometer my current cable is not cutting it. Another thing is what does everyone use as a cross member for the SM-420 and Dana 20 swap. I'm currently using the stock cross member but is there something better or more solid and simple out here?

 

these are all Jeep part numbers; should be available at any of the places that sell Jeep parts.
5351775 - 64.5" long
5351776 - 80" long
5351777 - 69" long
5351778 - 60" long
measure yours (overall length)
one of those should fit the bill.

 

Even one that is junk has useable parts. I bought a junk one for $10 a few years ago, the lower gears had sit in water the whole upper shaft of gears was good along with the tower and bearing retainer. These transmissions are all over around here.
I bought 7 of them 3 years ago for $75 a piece. Unless it has set in the rain the chances of it needing anything other than a general rebuild are slim and none. I doubt with a v6 or small v8 you would ever tear one of these up in a jeep, your entire drivetrain would go 1st. These transmisions were installed in eveything from dump trucks, school buses, motor coaches, pickup trucks, city buses and so on, there were literally hundred of 1000's of them made. Getting a spare one for parts is easy, as far as needing 6 of them to make 1 good one I doubt that very seriously, 2 maybe 3 at most. The 7 of them I picked up were all out of bread trucks (with very high mileage) and every one of them was perfect.

 

I put a 4.3 with a sm465 along with a dana 18
engine fit perfectly trans now that was no picnic lots of cutting of the floor to get it to fit right was even surprised to find the orig shafts still fit but still beefing them up anyways this swap was not fun to do by yourself like I did
didn't think it was going to go in now that pain in the azz is done now its the hydraulic clutch and exhaust and wiring it all up

 

Go with a t-18 out of a ford. easier to rebuild, plenty of parts much lighter then the sm465. I did one im my cj3b and love it, I've also done the sm465 and it's much more of a PITA to rebuild and is really big and heavy!

 

big n heavy doesn't tell the real truth its a boat anchor ,my 3b sits a inch lower now

 

Just finishing up the one in my 52 M38A1 and w/ small block and overdrive. Salivating, imo best bang for your buck for durability, size and low range and sure beats the ol 3 speed even though my t90 has survived 15yrs against my small block