Becca

Ok, so I've been told by numerous people that my 2008 STX- 4.6L V8, is geared tall (for MPG), and that if I put bigger tires (32.6"), it will eat up the tranny... I'm a bit freaked out to do this now. I don't want to re-gear it, cuz that's what I was trying to avoid in the first place (plus, it will void the warranty). I can take it out of O/D and run it that way... but I don't want to have to do that. Any thoughts, suggestions, advice???

brub27

I have the same truck as you and that is crazy talk that your tranny would get eaten up. You more than likely are runnin a 3.55 and 33's would not put too much strain on your truck. It will feel a bit more sluggish don't get me wrong but that is with any bigger tire upgrade. If you were goin for 35's+ then I would suggest a regear, but you should be fine.

brub27

What are you lookin into gettin?

Becca

305/65/17... roughly 32.6" tall and 2 inches wider than stock... with a 2" leveling kit

Becca

I don't know what to do...

boilerup15

I am running 325/60/18's roughly 33.4 x 12.8 with a 2.5" leveling kit. I dont have any problems at all. I think whoever told you that is crazy.. You should be just fine.

f150cwcw

It wont hurt anything. I have a 2006 F150 2wd with the 4.6L V8 and 3.55 gears like you have. I went to a bigger tire 4 weeks ago. I have 275/70/17's on my truck and that comes out to be a little over 32 inches tall. I have seen no difference in acceleration, and no lugging. You will be fine with those tires. The biggest difference i have seen is the fact that my truck rides a lot better. The more tire you have between the wheel in the road makes more of a cushion and makes the ride smoother over bumps in the road. I was going to go with 285's instead of 275's but the price jumped up to over $200 each for 285's and the 275's were $150 each.

f150cwcw

And to add to that, i also pull stuff quite frequently and i have not seen any weekness even while pulling.

driver444

Running tires that big may make the truck a little more sluggish as other have said, but keep in mind that the 5.4 trucks have the same transmission, and usually the same gearing, and they're not burning through transmissions. It'll just make the engine work a little harder. Probably won't be noticeable.

Yes, lower gears would make it easier on the driveline (engine included) in any vehicle, but you're still within range of what everything on your truck is designed to do.

wxmcpo

You don't need to regear running those tires, run your stock gears and you'll be fine. Just have your speedo and shift points recalibrated and you'll be fine. My dealership was going to charge me $80 to do mine. Or you could go with a tuner and some custom tunes which is what I did. If you move up to 35's that's when you really want to start thinking about regearing.