I have an '03 f350 and the trans fluid guage went hot and tow haul started blinking

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That light means that the shift points have changed on the transmission. This is to get better economy when hauling. If it wont stop flashing then there is a valve in the transmission that is bad or sticking. You will have to have it removed and overhauled..

Pull the main bulkhead connector on the side of the transmission and check for fluid inside the plug if so that shorting out the transmission electronics this is a common problem with ford transmissions if not check all fuses download the manual from ford owners.Com and your fuse box diagrams and fuse values are in roadside emergencies

Hi, I have a 2004 Dodge Ram 2500, 5.9 Cummins with 225,000 miles. Just today, my Haul/Tow keeps coming on and Trans/Temp light. Keeps automatically switching in and out on its own. It's been 100,000 miles since my last trans maintenance. Going to a mechanic close and he suggested to start with fluid change, filter change, and inspect the band, maybe adjust. Trans runs very smoothly. Checked the fluid, looks clean and not hot. Is this common with this year and mileage? If so, whats normally the out come? If the band is bad, do I have to replace the entire trans?


Scott

Yes it sounds like you have a bad transmission temp sensor.

climb under the truck! on the drivers side of the trans in the neutral safty swith unplug it and look for rotted connectors! if so repair damage! second go to passengerside near the rear of the trans ull see a plate that s being held by 2 7 or 8 mm bolts remove plate ! behind the plate there will b another plug do the same! inspect for corrosion

iam having the same problem did u figure it out

Does the trans fluid have a burnt smell and is it brown or dark brown as opposed to a red wine color? If this is the case then you may have a service issue caused by a clogged trans filter which is what this sounds a great deal like and the sooner you get the truck to the dealer or your mechanic the better as the trans in these are not cheap to rebuild or replace.

Check the wiring on the frame where it turns and goes to the trans, i have found a couple with chaffed wires and some of the wires run the trans temp sensor.which will cause both of these problems.

I would begin by checking the transmission fluid level. If it's ok, then that means that your transmission has overheated. Have it checked for overheating damage by a professional transmission shop. If everything checks out ok have them add a secondary transmission cooler. This will allow the transmission to cool down faster under heavy hauling conditions. Hope this helps, good luck!