Hello, need a tranny expert. I have a '03 F250 with a 7.3 and a 4R100 transmission. Intermittently the rpms will climb to about 2500 - 3000 before shifting into overdrive. Took it to the local shop and they changed the transmission fluid and filter, kept it and drove it for few days and said everything was working fine. I picked it up from them and when I finally got back in it to do some driving more then the few miles back home, I hopped on the freeway and it drove fine for about 50 miles with the cruise control set at 70 mph. When I stopped for a light in a small town and started down the road again it shifted fine until I set the cruise control again at 70 mph and drove about 19 miles and then with the cruise control still on the rpms jumped to 2500 again. So reacting to the jump in rpms I tapped the brake and just happened to be coming into town so I had to stop for a red light. When I took off from the stop light it wouldn't shift into overdrive, it would just go to about 3000 rpms and maybe shift into overdrive when I let off the accelerator. After that incident it will intermittently not shift into overdrive and the rpms will jump to 3000. I took it back to the shop and they drove it around and said that it was shifting fine. They said they did about 10+ start and stops and went to about 70 mph. When this issue initially reared its head I checked the overdrive off wire that I had read could be frayed or broken and needed to be repaired. Checked fuses and fluid levels, all fine. I continued to drive but eventually the transmission seemed to "lock" in 2nd gear and wouldn't let me go faster then 35 mph. When this happened I turned on the hazard lights and limped it to the shop. With reading on forums I have seen that the hazard lights being on can cause issues. I'm stumped as to what the issue could be. I have been reading that the torque converter locks in between 3rd and 4th/overdrive. Could this the a torque converter issue?

 

No, this is not a torque converter issue.

The first step to fix this is to read the codes. You can download Forscan free at www.forscan.org. You'll need an adapter to connect to the OBDII port on the truck. Their homepage tells how to select one.

Or you could take it to a good independent shop or a Ford dealer to read the codes. Auto parts stores that read codes free CANNOT read these codes.