2002 7.3 Powerstroke shifts out of overdrive too much when towing

22nd Dec 2016

Q: Good morning, I have a 2002 7.3 F350 4x4 with 373 gears and 90000 miles used specifically for towing a fifth wheel around 14000lbs. I have added after market exhaust, intake and diablo tuner, It also has a exhaust brake and manual lockup converter. My question I like to run around 67/70 MPH interstate and I cannot run in cruise as it will shift out of OD with any amount of grade. Am I asking to much of this set up and is there a option to give me more gearing as to be able to run in cruise. I previously owned a F250 7.3 with 410 gearing and could run in cruise about 70% of the time. I make a trip east on I40 to NC annually and with both these trucks there was considerable difference. Obviously going through the smokies and in other hilly areas I would run manually not using the cruise, I would like to know what if anything I can do to make my driving more pleasurable. Thanks Mike

A. Hi Mike,

I think the big difference is the rear end gear ratio difference between the trucks.  The other truck with 4.10 gears would down shift as soon as your current 3.73 truck.  When cruising in overdrive the 4.10 truck was turning a few hundred more rpm than your current truck and producing more power at the same mile per hour.  So your options are to change to 4.10 gears like your old truck had or add more power.  In the long run it would probably be less expensive to just do a gear swap.