Had 285/65R18 on my 04 STX 2.6 2v. Also had Billisteins 5100 and an add a leaf. Get the gears. It is a worthy step up.

 

You need more than gears if all you have is a 2.6 in that truck........

 

33's = 4.10's 35 = 4.56's these ratio's will keep you very close to stock. The difference between 3.73's and 4.10's is more than you think. With 33's and 3.73's as soon as you hit a hill shifts out of overdrive. Any long grade and it will be in and out of OD a lot heating up the tranny and eating gas. I have personally had multiple set ups in the past. Nothing beats proper gear ratio's for any type of performance and towing. Speedo would be off 10 percent and fuel economy by damn near 20. To each their own. get a bigger tranny cooler.

 

I've got 3.55s with 35's. Not exactly ideal, and yes I tow. I also have a much bigger than stock trans cooler, and living / travelling around Texas, hills aren't the issue they are for folks out west... Having said that, my future mod list includes selectable lockers and at least 4.10 gears, although I am giving 4.56 a serious look... I will never go bigger than 35's with this truck (my wife is 5' tall, and this is the largest tire I can jam in there with just a leveling kit). So I am not sure 4.56's are exactly right. Maybe if 37s would be down the road for me, but they won't...

 

4.56 and 35's are a good combo. I am going 4.56 with my 33's to help my little 4.6L 2v out. Ordered them last night.

 

haha it was a gen 1 ecoboost hate this phone, wife is always on pc! 35s are sooo much heavier than 33s. 4.56s for 35s all the way. 4.10s for 33s if running 3.55 or smaller. dewalt has the right idea for the 4.6 gas mileage is horrible when that engine is under strain. The extea rpms don't matter so much