Electrical Gremlin

[dwall]

Guys, I need some opinions on where to start trouble shooting this. The truck is an 03 f250 6.0. The truck has been used primarily as a sled pull truck for the last couple years, over the last few weeks. I have removed the kill switch and neutral light. The truck had weak batteries, but I was assuming it was from not being run for the last few months. I have driven approximetly 30-40 miles the last couple days with no problems. Tonight coming through town I stopped at a red light. While sitting there I heard a relay start clicking under the dash. I then noticed the tow haul light was flashing. When i took off, the motor reved the 3k before it shifted and it was a very hard shift. The truck started surging some while driving, which i assumed had to do with either the relay or the flashing tow/haul light. While driving I could still hear the relay clicking. I pulled into a parking lot where I could shut the truck off and see if that cleared the problems. Once the truck was off I waited about a minute, turned the key back on. I was going to wait for the glowplugs to cycle, but I never heard the buzzing that normally occurs at this time, when i turned the key on over to start the truck, and nothing happened. The dashlights all worked. I tried this a couple times with the same results. I then went to checking fuses. After finding none blown with the meter, i started pulling fuses to double check with the key on. When i pulled the ignition fuse i heard the glowplugs cycle, i tried the key and the truck fired right up. I cut it back off and tried again. It fired right back up. Once restarted the tow haul light came back on and while going down the road i gave it a little fuel to go up a hill, and the motor went from about 1800 rpm to 4k and bumped the rev limiter. I then noticed it wasnt pulling. I moved the lever to every gear selection and i just kept slowly rolling up the hill. I pulled into a parking lot, put it in park, then into reverse, and it back up. I then tried back into drive and it pulled just fine the rest of the way to the house. The only thing i hae done to the transmission, is a torque converter lock up switch. It is a three way switch wired where it can be run normally, unlocked, and then locked. I was running in the normal mode the entire time. Any one have any ideas as to where to start hunting this problem?

 

[CCRICE]

There is a relay I believe under the dash, someone might chime in and correct me. There was an thread about something similar to this awhile back.


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