RBPerry

My 2001 F150 has the 5.4 with 3:55 gears, and I'm pulling a trailer with a gross of 6600#. I was going to go to 3:73 gears, but think I want to go to 4:11 because of where we travel. We live in the Sierra's and travel over them and around them, we are in the mountains constantly. I'm not concerned about fuel mileage, but towing capacity.

My personal opinion is my truck was geared to high to begin with, but that is just me, I'm sure the Ford engineers are smarter than I am.

I see that a F250 with 4:11 gears can pull 9300 pounds, with the 5.4. I'm keeping my gross axle weight and tongue weight in check.

Any thoughts on going to 4:11 gears?

PerryB

Definitely go with the 4.11 ratio. The 3.73 isn't enough of a change to warrant the expense. I have 3.73's with 34.8" tires and I'm going to put 4.56's in mine.

Norotso

I'm not sure what body style you have but I had an 03 SCrew with 373 and our TT in my signature. We traveled lots through OR, MT, I'D and CO wasn't a tow beast and it sucked in head winds but did the job....

RBPerry

Thanks for the responses, mine is the crew cab 4x2 with 138" wheel base. I'm running stock tires 235/70 16. At 60 mph currently turns 1600 rpm in OD. I'm going to go with the 4:11 and if my math is right that will bring me to a little over 2100 rpm at 60 mph, and that is where the torque curve seems to come in on mine. I think the 5.4 is a great engine, was just geared too high for my application.

When I do it, I'll also do all the bearings and rebuild the limit slip, and new U joints.

Thanks again for your responses. With the 34.8 tires I can certainly see why you want 4:56, wouldn't that bring you back to about stock gearing?

Wife and I looked at the F150 EB and they sure are nice, but I can't justify 40K just to tow our TT, we have an Ford Escape to run around in.

PerryB

In my case 4.56 is actually over-compensating but that also helps with the increased rotational mass and suits my needs which is better towing in the mountains, same as you. Get back after the gear swap and we'll compare notes.
P.S. I'm just north of you a bit. We live in Chico and do a lot of camping & ATV'ing in the Chester/Mt. Lassen / Hat Creek area.

-- also, if your currently turning 1600 at 60 mph, the new number will be right around 1900 RPM.

RBPerry

I know your area well, Once lived up in the Browns Valley area, Challenge to be exact. I'm a retired truck technician, never seen anybody that can tear up a truck quicker than loggers. Are you running a performance chip in yours?

PerryB

I'm completely stock, performance wise.