The output shaft coming out of the rear end of my trans on my '91 formula 350 has some slop it in (.06") When I rotate the driveshaft by hand with the trans in Park, it makes a clunking noise in the rear extension cone. Is there a bushing or bearing in there that is worn out? Any help would be greatly appreaciated. Thanks. Chris

There is a bushing in the tailshaft housing. It is fairly easy to replace: The housing has to be out, and it should be done with a press.

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Thanks for the reply. Does the bushing sound like a good bet for being the problem or do you think it is something else?

There's also a bushing where the output shaft leaves the case. Is the play more side to side or front to back.

Check your U-joints first though... Also alot of backlash in the rear gears may clunk in gear. Also the early 700r4's had no accumulator for neutral (or park) to drive/reverse so they tended to slam into gear. Also too high an idle can cause this...

The play is side to side. Whats the best way to check the u joints. Right now I just grab the output shaft and drivshaft and turn them in opposite directions and look for play...is that the right way? I will have to check the rear end lash also. I have noticed that the rear diff. gets hot after driving, I don't know if this is normal or not. Thanks for the help.

It's better to drop the driveshaft to check for play as you may be seeing some lash between the splines on the output shaft, ect...

Just try twisting the u-joints in every direction and if there's any play at all they're no good. Sometimes they make a clicking noise when you try to twist them by hand. They are retained by injected plastic, so you need to melt the plastic with a propane torch if you plan on replacing them yourself. The replacements are held in with the snaprings or tru-arcs.