Went out for a maiden test drive and the transmission does not want to upshift into 2nd or drive. Has reverse and 1st, but nothing in between. I tried adjusting the kick down linkage in a couple of different settings , but still no change. Transmission was rebuilt last year by a local shop, that I've had do work in the past.
Fluid level checks good when up to temp.

Might have a stuck governor that is what i would look at first. If it were me i would probably replace it with one that had a higher rpm shift point to match my camshaft power band if i had to go in there.Get the 727 hand book very easy to read and very helpful .

if so may be able to fix without pulling anything apart????

https://board.moparts.org/ubbthreads/show...&PHPSESSID=

not sure, but checking governor pressures before may save some time
<2psi in D 0 mph...increase about 1 psi/1mph while in D

First, disconnect the TP linkage at the transmission lever and pull the lever full forward. Take it for a drive...if it still won't upshift the problem is in the governor.

Put the car up on jack stands , ran it up to 30 mph and hit the brakes. I did this a couple of times. Backed out the driveway , put it in drive and it takes of in 2nd. So now when I come to a stop it stays in 2nd . If you manually pull it down into 1st it will go into 1st, manually shift up to 2nd it goes into 2nd , shift up Drive it stays in 2nd. I ran it all the way up 50 mph and it still wont up shift. Could it be a problem in the vavle body?.

as the other members mentioned, check gov pressure, then the gov to see if is sticking.

O.K , I've got the tail housing removed . Do I need to take the snap ring and piston completely out of it's housing to check and see if its sticking ?.

Before you pulled the tail did you try disconnecting the TP linkage? Did you check the governor pressure?

Ya ,I tried it with the linkage unhooked with the lever in the forward position, still would not upshift. I didn't have a gauge to check the pressure. My next question is with the transmission sitting apart , should the governor piston/weight be out against the snap ring?. I've got about a 3/16" gap between the snap ring and piston/weight. Thanks for your help John.

The position of the components is different when there is pressure in the system....with no pressure the weight is subject to the laws of gravity.

Without a pressure check to make sure the governor is actually the problem all you can do is make sure the valve and weight are free to move.

The problem could just as well be a stuck valve in the valve body.

I pushed the valve and weight back and forth and it felt kind of gritty. That's why I was asking if the weight should rest against the snap ring, I didn't know how far the stroke was. I cleaned and lubed it up with a little trans fliud and it seems alot looser. Now it rest/falls against the snap ring. Hopefully that was the problem.

Check your coolant lines for kinks. A blockage or kinked line can cause what you describe as well.

Sheldon