Classic/Antique Car Repair: 350 Turbo wont go into drive, shift linkage, chevrolet 350

Question
I have Chevrolet 350 turbo transmission that will not go into drive, only reverse. I have checked the fluid and topped it off. Could it be a torque converter issue?

Answer
No, the torque converter has to be working or it wouldn't drive in reverse either.  The problem has to be internal to the transmission, unless the shift linkage isn't actually going to the drive position.  If  you can get your hand directly on the shift linkage where it goes into the transmission, see if it seems to be clicking into all the positions, and if it is, you know the problem is internal.  There are a couple of possibilities, but it really doesn't matter which it is, the trans will have to be diagnosed by a pro anyway.  It is possible the problem is in the internal linkage parts, in which case it can be fixed without removing the trans from the car - but the only way to know is to drop the pan and see what is happening in there.

Dick