I have a 1995 F250 XLT w/7.3 Turbo Diesel. From what I'm finding on the Internet it appears this should be an E40D transmission. I'll list some symptoms and then some background. Truck will go into Reverse and seemingly Neutral as it will move backwards in reverse and fail to move in Neutral. However, I cannot get it to go forward at all now, not D, 2, or 1. Some background: Some months ago I was driving it when I heard a pop and it seemed like I lost gears as it began coasting. I pulled it over, went through the gear shift a few times and it then took off when I revved it up a little. It then seemed to drive fine, however, I found when I got to my destination that the Reverse wouldn't work at that time. It seemed to drive forward OK. I drove it a couple more times on short trips in town before parking it for several months as I didn't have an opportunity to do much with it. Now the weather is nicer so I decided I'd see what I could do with it while I also had a couple days off work. I was able to get it to go forward, but seemingly reluctantly, but it did allow me to drive a circle in the yard a couple times. Reverse wasn't working initially, then I parked it again and the next time I tried it wouldn't go forward, but would go in reverse.
My dad suggested that I change the trans fluid and filter just as a first step. I know that it has been a long time since it was changed because I never had since I'd had the truck and I put limited mileage on it over the course of each year and never knew what was needed for that. The vehicle has just under 300k, most of that mileage occurred before I bought it used, but it has been a good truck really prior to this issue. I went ahead and changed the fluid and filter. I emptied pan (fluid was dark instead of red looking more like used motor oil). Magnet had quite a bit of buildup on it in my mind, but when watching videos online that seemed somewhat normal for an older truck with significant mileage. I used the method of unhooking the return line from the cooler to the transmission to help empty the rest of the old fluid. So I added 7 qts of fluid after the filter change and cleanup of the pan, including magnet, then I ran it while catching used fluid through a hose attached to that return line. After collecting a few quarts I then added 6 more quarts and did this again. I then added another 5 quarts and ran it one more time until it appeared I was getting new fluid instead of old and I estimated I had pulled out 16+ quarts of the old fluid between what I originally drained and what I had just flushed out. I don't know the exact quantity as I accidentally spilled some and had quite a bit drip under the truck. But I was relatively confident that I had removed 17-19 quarts overall. I then added 2 more quarts as the dipstick was showing low (one quart, ran for a while then added another one). So all in all I used 20 quarts of new fluid, but definitely pumped some of it out along with the old and the dipstick looked good at this point. BTW I did have my son move the shifter through the gears each time as I had added new fluid and was flushing out the old to ensure I pushed some new fluid through the various routes.
Despite this new filter and fluid the truck will only run in reverse (neutral does seem to work). I cannot feel it ever engage when we choose D, 2, or 1 but it is obvious that reverse engages when selected and neutral disengages when selected. Any suggestions on what I can try or should look for? I am not that mechanically inclined, but cannot afford to take it somewhere to be worked on so I am going to have to try to see if there is anything I can do to get it operational.
Thanks for any feedback you can give.
