2003 F150 towing Wildwood X-lite

I towed my TT with a 2003 F-150 5.4L Supercrew 4WD 3.73. I always used 3rd gear. It towed great at 65-70mph. I let speed drop to about 55mph before downshifting to 2nd. Your 3.55 will be a bit lower engine speed than mine. Mine was happier at 3000rpm than 2600rpm and thought 4.10 would have been perfect for that truck.

Dtaylor wrote:
The purpose of the tow/haul mode is to change the shift points to prevent the transmission from over heating. I use it when I tow.

There is no tow haul feature on a 2003 F150. You can only lock out OD.
And it does say in the pre 2004 manual to lock out OD when towing. And honestly. I very seriously doubt. The transmission will hold OD with the 3.55 rear. Just lock it out and relax. The engine will be much happier, making more power, giving you more throttle response, and not shifting down so much. And in fact. Getting better MPG, as the engine has to work harder to hold OD.

Thanks for the responses. And yes it is a 5.4.

The purpose of the tow/haul mode is to change the shift points to prevent the transmission from over heating. I use it when I tow.

dang, whats a Nissan motor doing in you're Ford?

Try it with OD activated. If it is constantly shifting up and down looking for the right gear (hunting) then keep OD off. Constant shifting creates excessive transmission heat and heat destroys transmissions.

With my van it is sometimes on and sometimes off depending on the terrain. Ford doesn't specify in the manual.

I have the same year and same truck , and I tow just about the same weight TT.
It says right in the truck manual not to tow in OD, so I never have.

If your truck doesn't have a transmission cooler, I strongly advise getting one installed

You can expect between 8 and 9 MPG, and you can also expect that it will labor on steep mountains, but you'll also be passing the tractor trailers that need the slow travel lane.

Jack L

Just sold my 2006 F-150 and we towed a 5,000K TT. OD is fine on the flats and slight grades (up or down). The best use I had for OD was to lock it out on the long medium grades, 3 or 4 % as it would hold me at a very comfortable 55 mph and you are not burning a drop of fuel. On the longer steeper grades (multi mile 6 to 8 %) forget about OD and I would just drop it down into second and we would roll down the hill at 50 to 55 again not burning a drop of gas but best of all, almost never having to touch the brake pedal.

When you see someone ahead repeatedly hitting their brakes on a long downhill they clearly don't know how to drive and of greater concern they are heating up their brakes which eventually is going to become a very big problem. OD is fine on any road as long as the tranny is not hunting (repeated downshifts), and will give you the best combination of performance and economy. :C

X2 there is no 5.6l v8 engine only 4.6l or 5.4l v8 for 2003 f150. I'm assuming yours is a 5.4l. IMO great tow vehicle considering its age.

I would lock O/D out and the engine is either a 4.6L or 5.4L if you want to change your signature.