Swapped the stock 265/60x18 tires and wheels with 275/55x20s. Based on the tire calculator the difference is 1.39". MPG dropped from mid 15s to low 13s. At the risk of showing my ignorance, is that enough to make that much of a difference in MPGs? If so, is recalibration a simple "plug & play" at the dealer?

 

Wow!! 120 views and not a single response! Nobody knows if it just simple trip to the dealer for a plug and play recalibration?

 

Try google. It will answer all of your questions and not burden anyone with retyping all the info for you.

 

I thought stock 18" tires were 275/65r18 or at least that's what's coming on mine. And if that's true the 275/55r20 is exact same size.

 

Close enough.

 

Really!! I thought this was a forum where you could ask questions and get answers. Sorry to burden you with having to type a smart a#@ response. Hope you never need a question answered. I'll be the first to tell you to google it!

 

I think it's a valid question, after all, isn't that what forums are for, to help each other out. There are a ton of people on this site running 33" and 35" wheels both of which would change the speedometer readings. How have you compensated for the extra size? I do see that the (2015 FORD F 150 Hypertech Speedometer Calibrator 742502) is available but is it necessary? Can the dealer reprogram this for you?

 

Mine's a 2wd so they are 265/60x18. 4wd come with 275/65x18.

 

Hypertech makes a speedo calibrater, When I talked to my dealer they said they can't do it I would have to buy a calibrated like hyper tech

 

This