I am currently shopping for a 2011 F 150 Supercrew with EcoBoost. 2.5 " LK will be installed. How will my MPG be effected by going to 285/65R18 BF Goodrich or 305/65/R18's T/A KO's versus the stock 275's.

 

Welcome to FTE!

You probably won't notice a significant drop with the 285/65/18.
The 305/65/18 will have a pretty good increase in weight of the tire itself, so getting it going, as well as stopping will take extra force. You'll notice 1-2 MPG drop I would assume with the 305 option you listed.
The 285 option you listed really isn't that much of a size increase, or weight for that matter.

 

Not sure how true this is but I was told at a couple tire shops here in the Denver area that the 305/65R18 BFG AT KO is on national back order.

 

Thanks guys. that's good to know about the back order on the 305's. I wasn't sure about the MPG, the 305's roll 617 rev's per mile versus 634 for the 285's but they are heavier. I'm ordering the 3.55 limited slip also.
Brian your truck is exactly what I'm going for. My current truck is a 2001 F-250 Supercrew, white/adobe two tone with 315/16 Wranglers, looks real sharp but I have a lot of tire rub on the leaf springs while turning.

 

Your truck and tranny will appreciate you more if you were to go with the 3.73 gears, especially if you plan to upsize.
Just my $.02

 

Renopat,
I would check some tire shops in your area just to verify that national back order...again that is what I'm being told in Denver. I had the 305/65R18s on my 2004 F150 and I loved them. To me it is a perfect sized tire for the F150 with a leveling kit. I went with the 325/60R18 on my 2009 just because I got them about $100 cheaper a tire then the 305 would have cost me at the time.

 

I agree, go at least 3.73's!!

 

The truck is on order as of 2 hours ago. I went with the 3.55 axle because of the limited slip option. I do a lot of snow driving in the Rockies and Sierra with never a problem for a lot of years.
So it's a Super crew Lariat, 6.5 bed with every bell and whistle except the navigation option. Two tone, oxford white and adobe.
My dealer said 600 vehicles are waiting for rail cars in Chicago.