Hi all, I'm in the process of re-gearing my 2001 F-150 for towing a 7,000 lb. travel trailer. My truck is a 4x4, reg cab, short bed, 5.4, 3.55 LS. I am trying to decide between 4:10 or 4:56 gears. I run 32" tires. I am not concerned about gas mileage since this is not a daily driver truck, used only for towing. I tow about 50/50 city/highway. When towing on the highway my max speed is 67-70 mph. I have done the V-10 transmission cooler mod and I have installed load range E tires. Looking for input from anyone with real world experience doing a gear swap on my vintage of F-150 for towing purposes. Thanks!

 

With 32's and a 5.4, I think 4.10's would be sufficient, and lock out overdrive. Don't forget to get a programmer, and I'd recommend custom tunes. You would be running about 3000 rpm in 3rd at 70 mph. If you keep the 3.55's, you would be around 2600. 4.56's would put you at 3350.

You know - considering a gear change will cost you at least $1600, why not just get a programmer with custom tunes and see how it goes? Overdrive should be locked out when towing that heavy regardless of gear ratio.

 

Thanks glc. I do have an SCT programmer with a custom towing tune. I did see an improvement with the towing experience since getting the custom tune, especially with the transmission shifts, but the truck just needs a little more "umpf" if you know what I mean. I think gears would do the trick. I do tow with OD locked out. After looking at the RPM numbers you provided, I am leaning towards the 4.10's. I think the 4.56's would just be a bit much at highway speeds. Re-gear costs shouldn't be too bad since I will be doing the job myself. I just want to make sure I get the right ratio that I will be happy with, don't want to do the job twice!

 

4.10/3.55 times current rpm at any speed you want to look at will tell you what the rpm will be with the new gears.

4.56/3.55 will work for rpm with the 4.56 gears.

 

It's easier to use an online calculator.

http://4lo.com/calc/gearratio.php

 

I vote for the 4.56 gears.

 

An 01. Short bed regular cab 4 x 4 pulling 7,000?

You need to look into that. I don't think that sounds like a good combo

 

A little late to the conversation, but 4.10's. Been there, done that with the same wieght.