I've been using my full sized bronco to pull my travel trailer for the past 10 years. Worked great. Well I got rid of the bronco and got a F-150, 4.6, 3.08, AT. Due to time constraints, price, and availability, I couldn't get a tow pakage, I've put it together myself except for the rear end. I really love my truck as is, good power, good gas mileage. I will pull only once a year and this year will be about 600 miles down the coast to Calif. some climbing. I was going to change the rear end to a 3.55 but have been thinking that I will leave it as is. The truck is now set up with trans cooler, elect brakes, class 4 hitch, weight distribution hitch. The trailer weighs close to 4000lbs. I will probably install a flip-chip before I tow. Does this sound like a plan or does the rear end have to be changed?

 

This should work fine, but you're off the line reaction time might be a little sluggish... (-:

Just watch for constant shifting in and out of overdrive. If the trans keeps shifting, which generates heat, just take it out of overdrive and you will be fine. I would also not plan on driving over the speed limit for vehicles with trailers since the faster you go with that load the more likely you'll overheat the trans. Putting on a cooler was a smart thing to do as well. Try it and if you're not happy you can always swap out the diff later.

 

IMHO, 3.08 is way too tall for towing a TT. You have to consider the wind resistance that you get. I think you will be in 2nd most of the time.

If I were you, I would try it out on a local freeway before making your long trip and then decide whether to change the gears while you still have time.

Ian

ps - If you are changing the rear end, you might want to consider 3.73 or 4.10 instead of 3.55.

 

I'm probably wrong. You may want to double check this in your manual. I think your truck is capable of towing up to 5,600 lbs. With passengers and other things, hopefully, you won't exceed this figure.

Chances are, with the 3.08 rear, you won't be winning any races. On the other hand, once you get rolling and are on level ground, you should be just fine. As others have mentioned, you can try leaving it in OD, but once you find that you're mashing down on the gas pedal and causing the OD to knock off, you will want to turn the OD off.

You most definitely will want to try towing with your present setup before you think abotu a gear change. For all you know, your present setup might be what you really need. Why invest more money when you may not even need to?

 

Had the same truck, towed about the same with no problem. Just keep it out of overdrive in the hilly country. It won't hurt it to run 500 rpm higher. (Same as installing a lower gear). Good point about the speed. Anything over 75 and mine would constantly kick out of overdrive. Just to be safe, load it and have it weighed and make sure the weight is within the limits of the owners manual and you'll be ok.

Good luck.