i noticed that my yoke wasnt in the tranny very far, only on like 3/4 of an inch. so i was going to have my drive shaft lengthened, the guy at the shop said to put the yoke in untill it bottoms out, pull it about 3/4 of an inch, then measure u-joint center to center. well, i pulled the driveshaft and went to put in the yoke till it bottoms out, but it only goes in like an inch. i dont know whats wrong. i bought a th-400 yoke from a junkyard, which has all the right th-400 dimensions, and i know that i have a th-400, but they dont work. i called the driveshaft guy and hey said to line up the slot. the yoke has a slot that looks almost as if one of the splines is missing, which I know is meant to be like this. i looked on the tranny output shaft for this corresponding slot, but i cant find anything, the splines just go all the way around. does this make sense? thank you for any help.

 

The "missing" spline doesn't matter.

Sounds to me like your trans has a new bushing (recently rebuilt?) and it fits real tight to the yoke. You may just need to push a little harder. It should go in 4" or so, maybe even a little more depending on which yoke you have. You can take off the extension housing (4 bolts) and see how the yoke fits in the bushing. There may be a little burr of material on the edge of the bushing, from the install process.

 

no, its not rebuilt, but i read on a searched thread a guy replaced his bushing and it fixed the same problem. ill pull the tail shaft and check it out. thanks

 

You might have to turn down the yoke or get a different kind. That happend to mine, it would only go in so far then stop. Took it back to the driveline shop and he turned it down, slipped right in after that.

 

i just took some emery cloth and cleaned it up a bit and it worked fine. thanks for the replies