So I have the car in the title above.  It’s got high mileage, 209,000mi and the transmission has been replaced once at 100,000mi.  I know these transmissions are notorious for only lasting about 100k from what I see on various forums.  

So, anyways, one day I went outside to drive it and it went into gear just fine and I was backing out of the driveway and when I put it in drive.......nothing.  I put it back in reverse........nothing.   So I got my boys to help me push it back into the driveway.  It sat for a week or so and I went back to tinker with it and checked the transmission fluid which was where it was supposed to be.  I got in it and same thing, it went into gear and I backed to the end of the drive, then put it in drive to pull forward again just to test it.........nothing again.  

So, it will move for the first minute or so it runs after sitting for a few days, then not again for a few more days and then same thing all over again.  What is going on!?  New transmission time again?  If it is I’ll probably get rid of the car cause it’s not worth what it’ll cost me to replace a transmission.  Anyways, thanks for any help/advice you may have.

Check to see if the shifter cable isnt broken or out of adjustment.  I'm guessing it would have one.

Just to make sure, when you're checking the fluid the car's parked on level ground, running, and in park?

Have you tried dropping it down into 1st 2nd or 3rd?

Yes it is, thank you for checking though!

Yes I have, nothing there either unfortunately.

Thank you, I have not checked for that yet! I know NOTHING of transmissions either, so I apologize this is like talking to an idiot!  

If it is a 4T65 they break pump shafts real easily. Even in a V6 replaced a lot of pumps and shafts.

None of the FWD transaxles are really strong enough to handle a 5.3.