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| | | | Joined: May 2011 Posts: 6 New Guy | | New Guy Joined: May 2011 Posts: 6 | Does anyone know where I can get the speedo gear that goes on the output shaft of the three speed trans in my 59 GMC 1/2 ton. Rear axel is a 3.07. Cleaned lubed and checked everything else all OK but still doesn't work. Thanks | | | | | Joined: Apr 2005 Posts: 2,097 'Bolter | | 'Bolter Joined: Apr 2005 Posts: 2,097 | If it is an SM318 (which is the same as a Chevy) I have several drive and driven gears for them. 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
| | | | | Joined: May 2011 Posts: 6 New Guy | | New Guy Joined: May 2011 Posts: 6 | Fred- thanks for the reply. It's the orginal three speed. 1959 GMC 100, 270 L6 I'm not sure how to determine which model it is. If you can help let me know. I need the gear that goes on the tailshaft that drives the speedo cable adapter. How much you asking for one of the gears if you think you might have the correct one. Thanks for your time. Dave Enders
| | | | | Joined: Apr 2005 Posts: 2,097 'Bolter | | 'Bolter Joined: Apr 2005 Posts: 2,097 | Dave,
The SM318 has a 4 bolt side cover and is about 22" long measured from the bellhousing mount to the end of the tail shaft. There was also a Warner HD trans available which has a 9 bolt side cover. GMC also used a 3 speed that looks to be something similar to the trans used in a Buick or Pontiac. It's shorter than the Chevy trans but thats all I know about it. I'll donate the gear to the cause if it will fit what you have. Give me a call 562-225-5869
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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