As of now we have Contis (stock 275/70 R18), which are good tires for the road, but lack in other categories: we really likes the BF Goodrich all-terrain KO that we had on our previous truck (05 F150) and they are probably our #1 option, but i still have a few questions:

1) what kind of sizes can i safely run on the stock rim (truck also has the fx4 package) as the wife mentioned that a slightly taller tire might look better
2) would mileage suffer considerably?

Thanks

 

Mileage will go down, 0.5-2mpg depending on how big you go. I wouldn't go wider than 305 on the stock rims. Tallest you could go without rubbing issues is probably a 285/75/18 which is a narrow 35" tire (narrow being 11.5").

 

I have been pondering the same question. I have an 05 king ranch as well w/ the stock 18x8 rims. Wanting to upgrade but can't make up my mind. Would love to put the BFG All Terrain 305/65/18's but don't know if they will fit width wise on the rim since they recommend an 8.5 - 11 inch wide rim and mine is only 8 inches. Plus I would prefer not dropping in the height of the tire but that's the only option on the BFG's. I have been thinking about the Toyo Open Country MT's 315/70/18 or 285/75/18's which would give me width and height (sounds like I am compensating for something, uhhh whatever) but I don't really need that aggressive of a tire, not too mention both are more than the BFG's.

I guess my biggest question is will the BFG 305/65/18 fit on a stock 18x8in rim and not have tire rub (have aftermarket suspension but stock height)?

 

It'll probably be okay, but its a little wide for the wheel. The Toyo AT also comes in the 285/75/18 and is a VERY good tire.

 

35x12.50x18's on compete stock F350.

 

we were thinking between 285 and 305: nothing wider

 

I've been thinking of getting the Xtreme ATs in 37x12.50 next, how do you like 'em?

 

So far I love them. Great in everything I have put them thru. I can't wait to try them out in the snow. Wet mud and gravel, heavy rain, plowed fields no problems what so ever. So far I can't even see any wear.