Bill,
My '60 was a factory 3spd, original owner swaped for SM420. Great box if you want to use it as a work rig. Too large of a ratio change from 3rd to 4th for me as a hiway rig but will give the 235 stump pulling 1st gear. Had a M20 Pontiac 4spd in it for several years, loved that 3rd gear acceleration to road speed. Down side, way too high 1st & rev on hill. Been running a T5 about 4 years now, should have swaped sooner. Mine is has the lower 1st gear ratio, not the best if I was always on the streets but give much better back road ability. I'm, running a 3.56 spicer rear end, pulls good in 5th down to about 60 mph and sure cuts down on the engine noise. The newer 3spd will stop that grinding when shifting to 1st rolling and that's the about it. As long as the 3/4 ton 4spd, as long as its as SM420 ('67 back) it will fit. Repair of the o.e. unit may be the simplest & cheapest option.
BC
Last edited by BC59; 12/17/2011 9:13 AM.
