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| | | | Joined: May 2005 Posts: 10 New Guy | | New Guy Joined: May 2005 Posts: 10 | Hi, I took the old 3 speed manual trans. (with the granny low) out of my '57 3100 in favor of an automatic and now I want to sell the old 3 speed. I'd like to know what exactly it is when people start calling me and asking.... are there I.D. codes on the trans.? I found a few sets of numbers and letters like GM18 and 591668, K956 and GM591953, K1256 T. Any help is appreciated, Thanks | | | | | Joined: Jul 2004 Posts: 5,708 'Bolter | | 'Bolter Joined: Jul 2004 Posts: 5,708 | flyinv55, I might be all wet on this, but if your transmission has 'granny' in it, it would be more correctly referred to as a 4-speed....a SM-420 by name. This is a very popular (or was) transmission with Jeep people, and just a general all around good tough transmission. Good luck with the sale of your Muncie SM420. http://www.novak-adapt.com/knowledge/sm420.htmStuart
Last edited by atomarc; 11/01/2007 5:35 AM.
| | | | | Joined: Apr 2005 Posts: 2,102 'Bolter | | 'Bolter Joined: Apr 2005 Posts: 2,102 | If it has a 9 bolt side cover it is a Warner HD 3 speed. They are about the same size as the SM420 4 speed and low gear is really low. Good HD trans but not very common or popular.
If it has a 4 bolt side cover with a long tail shaft - total length of the trans is 22", it is a regular 3 speed also known as an SM318. Lots of them out there.
Fred
1956 3100 Pickup/Red/350/3sp OD/PS/Disc Brakes
1957 Bel Air Sport Coupe/Red/355/TH350/PS/Disc Brakes
2017 Silverado LT Single Cab SB/Black/5.3/6 Speed Trans
1947 Willys CJ2A w/F-Head engine
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