OK I have a 99 f250 5.4L 4x4. Was out of town for a few months on a job while the wife was driving the truck and first day back she called and said truck was in drive and wouldn't drive anymore, while waiting in a line. Towed it home to find fluid wasn't showing on dipstick. Added two quarts of tranny fluid to get to proper level. While truck is in park the transmission makes a grinding noise, once I put it in any other gear truck doesn't move. What's y'all thoughts? New tranny or a easy fix?

 

Sounds like it's time for a rebuild or a new transmission to me.

 

A grinding noise is the sound of death. Not good news.

D

 

Rebuild it! Can be done in a weekend. Get your rebuild kit kit, bearing kit, TC if you are going to replace it. I replaced all wearing items so I wouldn't have to go back in. Get a new shift solenoid and pressure regulator, a Sonnax Sure Cure valve body kit, and a SHIFT supertuff separator plate. The 2-3 accumulator has been updated, the rubber on your OD accumulator will be hard, and the 1-2 accumulator will wear and it's the most used. I would recommend to replace all.
All parts list will correct any short comings of current parts.
The transmission bench on YouTube will give you step by step instructions. You'll need a god set of snap ring pliers, and a special press. Watch the videos before you do it. And build the press before hand. It works fine. You'll need two 2x4's and some bolts.