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Transmission shifts hard tow/haul light flashing

20207 Views 6 Replies 2 Participants Last post by  Mark Kovalsky
I have a 2007 F250 6.0. Monday of this week got ready to leave the house to go to the store let the truck warm up and when I put the truck into reverse the tow/haul light started flashing and the engine stalled out after doing some research on here found a thread about replacing the transmission fluid temperature sensor. Replaced the sensor and filled it back up with Mercon SP. Test drove the truck it shifted good. Then drove the truck to the store put fuel in it and on the way back home it died on me with no hesitation or warning after some testing found out the starter was bad replaced starter on Friday and truck started up and ran ( still not sure how a bad starter caused it to shut off like that ) drove it to advance auto parts for a charging system test and the tow/haul light started flashing again and started shifting hard. Turned the truck off and let it sit drove fine with no flashing tow/haul light for about 2 miles then it came back on. MIL is not on. Any help on this would be greatly appreciated
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Changing the temp sensor was just a wild guess. It obviously was not the problem. You need to get the codes read to find out what's really wrong. The places that read codes free CANNOT read the codes you need. Take it to either a good independent shop or a Ford dealer.

The codes stay in memory for about a month after the last time the light flashed, so don't let them tell you the light has to be flashing to read the codes.
P0700 is the only one that is on my transmission list. That code means the computer recognizes SOMETHING is wrong, but doesn't have enough information to tell WHAT is wrong. It only confirms that you have a problem.

It make take more driving to set a code that will help.
P0741 and P1744 both say the torque converter clutch is not working. That could be a bad torque converter, a stuck valve in the pump body, or a bad seal on the input shaft. I don't know how to determine which one without taking the trans out and tearing it down.
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