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4 speed transmission question #934998 04/11/2013 9:54 PM
Joined: Jul 2010 Posts: 27 TEXAS T texman 'Bolter
texman 'Bolter T Joined: Jul 2010 Posts: 27 TEXAS	question - how new of a model 4 speed open drive shaft transmission will bolt up behind a 1952 248 gmc engine ? redoing drive shaft would be no problem. looking to upgrade using original bellhousing thanks texman Last edited by texman; 04/11/2013 10:16 PM. 1940 GMC AC 302 1 1/2-Ton Dually BOHEMIATH In the Stovebolt Gallery More pix in Flickr

Re: 4 speed transmission question texman #935003 04/11/2013 10:17 PM
Joined: Nov 2005 Posts: 6,100 B. C. Canada 3 3B 'Bolter
3B 'Bolter 3 Joined: Nov 2005 Posts: 6,100 B. C. Canada	Hy texman, if you want a four speed with a p.t.o. opening and capable of some work, then the SM420 would be a good choice. If you want something with overdrive in a light duty truck, then a T5 may be more what you're looking for. The T5 takes some adapting, the SM420 is a bolt in, hope that helps.

Re: 4 speed transmission question 3B #935022 04/11/2013 11:10 PM
Joined: Jul 2010 Posts: 27 TEXAS T texman 'Bolter
texman 'Bolter T Joined: Jul 2010 Posts: 27 TEXAS	I would rather go with something that would bolt up to what I have now . what 's the newest year model SM 420 whats trans that that would bolt up ? Texman 1940 GMC AC 302 1 1/2-Ton Dually BOHEMIATH In the Stovebolt Gallery More pix in Flickr

Re: 4 speed transmission question texman #935027 04/11/2013 11:50 PM
Joined: Nov 2006 Posts: 247 Gunnison Colorado J J M 'Bolter
J M 'Bolter J Joined: Nov 2006 Posts: 247 Gunnison Colorado	Texman I believe that 1967 was the last year that the SM 420 was used in the light trucks. It is a great transmission if you aren't looking for an overdrive to get more speed. Good luck Jim

Re: 4 speed transmission question J M #935124 04/12/2013 12:43 PM
Joined: Jun 2011 Posts: 5,096 Longmont, CO E EdPruss Crusing in the Passing Lane
EdPruss Crusing in the Passing Lane E Joined: Jun 2011 Posts: 5,096 Longmont, CO	SM-465 started in '68, comes in different retainer and input shaft sizes, lots of them out there, NP-540,1,2 5 speed(OD rare, gap in ratios) works well if loads to pull. '37 GMC T-18 w/ DD 4-53T, RTO-610, 6231 aux., '95 GMC running gear, full disc brakes, power steering, 22.5 wheels and tires. '47 GMC 1 ton w/ 302, NP-540, 4wd, full width Blazer front axle. '54 GMC 630 w/ 503 gasser, 5 speed, ex fire truck, shortened WB 4', install 8' bed. '55 GMC 370 w/270, 420 4 speed, grain, dump bed truck from ND. Works OK.

Re: 4 speed transmission question EdPruss #935179 04/12/2013 5:01 PM
Joined: Jul 2010 Posts: 27 TEXAS T texman 'Bolter
texman 'Bolter T Joined: Jul 2010 Posts: 27 TEXAS	thanks a lot guys ! texman 1940 GMC AC 302 1 1/2-Ton Dually BOHEMIATH In the Stovebolt Gallery More pix in Flickr

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