Transmission Temperature Goes Up and Engine Loses Power on a 2002 Ford F-350 Diesel

Updated 10/07/2015 | Published 10/06/2015

Question:

I have an 8inch lift with 37/13.50 tires on my f350 diesel. When climbing hills without pulling a load my stock transmission temp gauge goes into the red. I have a bullydog chip and its telling me the temp is 140. So I seem to think the issue is with the stock sensor in the truck? Also climbing long steep hills in the rocky mountains the truck does not like to go over 100kms/hr 60 miles an hour. foot to the floor and it doesnt want to pull through it. do you think I am having turbo charger issues or something else may be the problem?

asked by: Codey

Expert Reply:

Any time you add larger tires to a vehicle it makes it harder on the vehicle and more power is needed to do the same amount of work. It happens all the time to Jeep owners.

First, if your 2002 Ford F-350 has a stock tow/haul button be sure to use it when towing. The programmer you are using should probably be set to tow mode or heavy tow mode (if there is more than one tow mode) when towing as well.

Regarding the transmission fluid temperature I have not seen a vehicle that had a stock transmission temperature gauge. Coolant, yes, but not transmission fluid. But if it does have a stock gauge that is going into the red then I would have that checked out since the programmer is giving you a different reading. It is better to err on the side of caution.

If it is coolant then it could be air in the lines. I had a vehicle that would get hot at an incline. Usually to get air out you would park the vehicle so that the front is higher up than the rear. Remove the radiator cap (cold), start the truck and turn the heater on full. The fluid will go through the system, pushing any air up and out at the radiator since air wants to go to the highest point in a closed system.

If the issues still are not resolved then use the programmer to return the truck tune back to stock to see if still has the same problems. If it does not solve the problem, keep the truck in stock mode, remove the programmer, and have a Ford technician give it a good once over to determine the problem.

expert reply by: Michael H