what linkage can i use to make the manual trans from the 1981 truck fit into my 75? should i use the 75 linkage or the 81? is the 81 a hydraulic setup? Also how much shorter is a t-18 trans when compared to a c-6?

 

You will need the linkage from the 1975. I know there are slight redesigns in the linkage for the 1980-1981, in the cab. The 81 uses a manual linkage though, so no worries about having to retrofit a hydralic setup.

Check the rod that connects the linkage to the clutch pedal on the 75. they are known to bust off at the pivot points. look for cracks and if suspected of damage replace. Don't want you driving 100 miles from home and then have the clutch pedal fall to the floor.

One thing you can use is the 1981's linkage adjusters. They are threaded on some models so they don't fall apart as easy. Some 300-I6s of the 70's used to have dropping clutch linkage syndrome. The treaded adjuster eliminated, or made it easier to put back together when or if it did happen.

As for the length of the tranies, I don't know. The drive trains of these trucks, If they are both 100's or 150's are very simular and swapping the driveline out of the 81 may be the only thing you need to do to get the lengths right. Of course it all depends on if it is a short or long bed and the length of the wheelbase etc...

hope this helps

P.S. Private messenged you about some questions of my own conserning the 1981.

 

thanks.

the truck is missing all the emissions items and the smog pump is frozen. i don't think this would by a good choice for any spare smog parts. mike

 

Ah, well, had to ask. thanks anyway.

good luck with your project.