I have a 99' F150 Lariat with the 5.4 and tow package. I am currently putting a 4-5" inch Rough Country Lift and 35" Mickey's on my truck. I have an 18' car trailer that i pull Demo Derby cars with. The truck seems to have plenty of power to spare, but I don't know much about gearing and the effects of big tires. Do ya'll think i'll be ok without gears? If i need new gears, what ratio? All info is greatly appreciated!

 

with a lift, and 35" tires I would definatley say 4.10's and possably 4.56 gears especailly with towing an 18' trailer, but just my opinion.

 

4.56's for sure

 

Eh I think with a 5.4 you'll be okay without gears. Obviously gears will make an improvement, but I'd say for now save that money and spend an extra $150 on an RCD lift instead of Rough Country.

How heavy is the trailer you're towing?

 

If you are towing a car, Im assuming for demo derby its going to be a heavy steel paneled car, I would definitely go 4.56's

 

Try it without regearing - if it performs acceptably to you, why spend the money?

 

I know I wouldn't want to with my 5.4 with 3.55 gears currently on my 04.

 

I have 3.73 gears, and i have no idea how much my trailer weighs. Its a double 3000lbs axle, 18ft dovetail. I know regearing is very expensive, but will towing without gears hurt my tranny. I drive it right, no hard driving.

 

Its gonna be jumping in and out of OD cruising down the highway at the slighest change in elevation, acceleration, etc. I have yet to re-gear mine but with the way it drives right now regulerly, I really wouldn't want to be pulling a car trailer. Granted you have 3.73's and I have 3.55's but I don't think that would make a huge difference. Not to meantion your gas mileage and power are gonna be pretty bad.

 

So you turn off the OD - it will prolly get better mileage than if you let it shift in and out - and it will definitely be easier on the tranny and have better response.

 

i personally would have went with the gears first instead of a lift. Beef that drivetrain up!! if you are going to be pullin a trailer around, does 4" of lift and 35" tires help pull that load any easier? now you are goin to need a drop hitch unless you have a 5th wheel.
but you can try your current combo with the gears, and see if you really need to spend the money to regear. if you only haul the trailer around 2-6 times a year, and dont mind takin 10 minutes to accelerate up to speed, go with that. it is all up to you and how comfy you feel driving and towing.

Just my $.02

 

I am fine with it taking a while to get up too speed. I only haul to places that are no more than 2 hours from my house. I do it about 15 times a year. I just wanted to make sure that i wasnt going to mess up my tranny or motor by doing it. But if push comes to shove, i'm gona regear it. Would 4.88's be to much?

 

If you do end up gearing, 4.56s would be just right. If you have a 2wd then you can get 4.30s, which may be a better choice. I agree with glc though. Just try it out stock and see if you can deal with it. If you decide you want to regear after that then do it. No sense in spending $1200+ if you don't need to. And as far as your tranny goes, just get a good cooler and it should be fine.