SM420/con-diesel

SM420/con-diesel (pictures added)

I have recently acquired an NOS con-diesel SM420 which I would like to use in place of my current SM420. Is there a guide or reference detailing what is required to convert the top plate and any other components? The configuration is Chevy 5.7 to SM420 to Atlas.

Thanks,

g

 

Pics? I've never heard of a con-diesel SM-420. Is it more than just a standard SM-420? There was two versions of the SM-420 made, an early and late version. I'm not sure where the break was. Maybe someone can chime in... If you can post a pic of what you have it would help a lot. Good luck

 

I don't have any pictures, but I will get some. The con-diesel version of the sm420 was the last version built. They had a remote shifter top, no PTO, and some optimized internal parts. Which ones - I do not know. I believe they were produced into the late 70's, perhaps early 80's - but that's a guess. I will have the serial number checked to confirm the date.

g

 

Huh, new one on me too..

 

What did it it come out of? Try and find the newest normal SM-420 see if the shift tower will interchange. Check out the input shaft and see if it matches as well. Most adapters will require a new output shaft so you can change it around to suit what you need. Since you already have a SM-420, it might be easier to just freshen it up.

 

Novak conversions may have some information on these transmission, I remember reading about them on their site.

 

To my knowledge the 420 was manufactured from 47 to 67. 47 to 53 is considered the older and 53 to 67 the newer style. The 47-53 era input shafts had no seal in the bearing retainer to keep the gear lube inside. All they had was some grooves, kind of like the grooves for a speedometer gear, that were supposed to act as slingers if you will to keep the lube slung backwards. Not very effective and the result was a lot of lube soaked clutches. I've never heard of them being manufactured after 67; looking forward to the pics.

Mike

 

According to the Novack site, the Con-diesel version was made as late as the early 80's. Here are a few photos. Note the remote shifter top. I will be sending this to Novack for inspection, set-up, and a new top cover.[/URL][/IMG][/URL][/IMG][/URL][/IMG][/URL][/IMG]

 

According to Condec, the Con-diesel version of the sm 420 was used in the Gamma-goat