I have a 2000 7.3 Excursion all stock. Last year when I was launching my boat I put it into drive to drive off the ramp and the truck wouldn't move. I had to be pulled off the ramp. It wouldn't engage drive at all. It would just rev the engine with no engagement. I did however have reverse. So I checked the Trans fluid level which was all good. I checked the linkage under the truck and that was good. So I had the truck towed. A few days later I went to pick up the truck and have it trailerd home and it acted fine. Drive would engage just as it had before. My guess is that once it cooled it was able to engage. So when I got it home I tried to trouble shoot. I dropped the pan and the fluid smelled bad but there really wasn't any debris in the pan or on the magnet. I also checked the three bolts on the valve body and they were tight.

So I parked the truck in storage and didn't pull it out until just a few weeks ago. I fixed one of the issues with the turbo and now I need to focus on the Trans issue. It will engage in drive. I have driven it only a few miles without pulling anything. When I take off from a stop it shudders and the whole truck just shakes for a few moments. Then I drives fine and shifts as usual. It doesn't happen when braking only at take off. I have a stock truck with no lift suspension so the drive angle should be just fine. I have a one piece drive shaft so I took the shaft off and greased the spline going into the back of the Trans. I also added 8 ounces of Friction Modifier to the rear diff. I don't believe the problem is the splines or the reared. I believe it is the Trans. I want to sell the truck because we no longer need such a big vehicle since we got rid of the boat. But I can't sell it with this problem, it just wouldn't be the right thing to do. What are your thoughts?

 

Time for a trans rebuild. Mine did this years back. Reverse no forward. Then forward worked then only second gear. I bit the bullet and had it rebuilt. It is common with the 4r100 transmission. I'd say put the money in it and keep it a while. All else being good.

 

There's nothing wrong with selling it as it is, just disclose that it has the problem and let the buyer decide how he'd like it fixed. He might want a cheap rebuild, or something higher end, or might be a DIY guy that appreciates getting the truck cheaper than if it had a rebuilt trans installed.