I have an 88 transam GTA and I have a problem. When I put first or reverse on it, I would hear a clunk. Aside from that, everything works fine with the transmission. I thought it was the universal joints, so I decided to replace them. When I took away the drive shaft to replace the U-joints, I noticed that the transmission output shaft was loose. Is it supposed to be that way, or it is supposed to stay put? I would like to know if there is something wrong. If so, is too difficult to fix?
I would appreciate any help. Thanks

 

Do you mean loose when the yoke is out? If so, yes.

Do you mean loose when the yoke is installed? If so, it should move in and out, but not (much) up and down or side to side. The yoke tube is a bearing surface to a bushing in the transmission tailshaft housing. They do wear, especially if the ujoints are shot or the shaft is out of balance or not completely straight. The bushing can be replaced, but the tailshaft housing has to be removed to do it.

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