I know three types of those trans were made and I am looking at one in a 81 F150 that has internal shift linkage and wondering if it had the big ratio jump between 2nd and 3rd like the rest of them. If it has the normal 3 speed ratios and o/d in 4th I might look into buying it for a future project,one would think it would since the truck came with 2.75 gears.

 

I have a 79 super cab with a 351M and 3 speed tranny. Is it easy to put a 4 speed and if so what's a good one for that year? Thanks

 

You can put in any tranny that will bolt up. Small block to sb, bb to bb. Your problem will come with finding the right age. In 81/82 somewhere in there they went to hydraulic clutches in some trucks. Now if you can snag the stuff off a donor truck you can get pedals, mc, lines, drive shaft, crossmember, clutch, etc... Then you could use up to a 96 5spd. Thats what im after.

 

Jeff if you can get a pic of the door tag you can decode the tranny if its the original. If you need post the pic here and i can get a buddy to tell me about it.

 

The 81 has a mechanical clutch linkage which I will be grabbing but I would like to get the trans but wondering if it has that big gear spread between 2nd and 3rd.