Transmission to Driveshaft Coupler

[bybirius]

I think I might have screwed up on something. I saw a picture somewhere of the gear on the back of a 4 spd transmission that had a cone shaped bolt head with a spring on it. It looks like it's supposed to help center the driveshaft coupler? I'm not sure what the spring is for, maybe to keep the driveshaft coupler from moving back and forth. Anyway, On my transmission there was only a regular looking bolt holding that gear on. And when I put it back together, I used that same bolt...Should I be worried about that? Should I pull all that apart...ugh! and replace it?

Thanks,

[Bob C]

There is a picture on page 415 of the Service Bulletins.

Bob

[Farrell In Vancouver]

I believe the spring is there to keep the internal and external teeth meshed together. One coupler shaft I pulled down did not have that spring and pointed bolt installed, and the teeth on both parts were badly mangled and could not be reused. The lack of the parts also cause the shaft to jump around which took out the shaft tube and grease cup.
If you're not too far ahead I would tear it back apart and get the right bits in there and save some grief further down the road.
Best regards.

[bybirius]

Thanks for replying. A picture is truly worth a 1000 words. Yeah, I'm about as far ahead as you can get. Guess I'll be cracking it open again though. Since I'm going to get back into all that I'd like to replace the gear and drive shaft coupler as well. Anyone know where I can get those things or will I have to get them made?

[Bob C]

If your going to replace the coupling shaft I would go with the service
replacement one with the u-joint at both ends.

Bob

[bybirius]

If your going to replace the coupling shaft I would go with the service
replacement one with the u-joint at both ends.

Any idea where I could get this?

[tiredtruckrestorer]

Make sure you look close at the drawing that Farrell in Vancouver posted. Note that the rear knuckle of the u-joint assembly has a stop made in the front of it it to keep the coupling shaft from sliding back and forth too far. Without this stop the whole assembly will be sliding back too far on the drive shaft splines. This will also cause excessive wear on the transmission couple shaft gear and mating coupling shaft itself. If you put the spring and cone headed bolt in like it supposed to be, then make sure you used the right u-joint with the collar (stop) in the splines.

Keith

[bybirius]

Is that collar a disc? Is it a C ring type of clip? In other words: If mine doesn't have the stop, is it something easily fabricated? I've searched online high and low and can't seem to find these parts, so once I get everything out I'm taking them to a local machine shop and see if they can make some new parts (An expensive endeavor I'm sure). Don't know yet if the U-joint I have is the one with the collar. Not sure how to make it or the bolt and spring without seeing them.

Hey Keith, if you're going to be in Hershey in October and you have some samples you could show me, I'd love to take a look at them.

Thanks,

[tiredtruckrestorer]

Mark, if my memory serves me right, the rear yoke (Ford calls it a knuckle) has a washer installed at the front edge of the splines. Probably could tack weld one in your yoke if you had to. I'd be glad to bring some samples along for you to look at. I'll check if I have extras and maybe I could help you out with the needed parts.

Keith

[bybirius]

Thanks Keith, I bet you're right. I'll check that when I pull it. Look forward to meeting you.

[bybirius]

Well, I took it all out...wasn't that bad. There looks to be a stop on the rear knuckle like you said. The gear on the back of the transmission is showing little to no wear but the driveshaft coupling is another story. I think someone before me replaced the gear but used the old coupling. There's a lot of slop between the gear and the coupling. I don't know what I was thinking when I put that back together. Okay, maybe I wasn't thinking. Anyway, I need a new coupling, a pointed bolt, and a spring. Or a coupling with u-joints on each end.