So the dealer says it can't be done, i believe it has to be possible. With all the technology this vehicles have you mean to tell me Ford has no way to change the setting to adjust for bigger tires?

So, any Ford techs in here that can confirm this being true. Or that know it can be done and care to explain how to do it. I believe is with the Ford ecu tool the mechanics have.

If it is possible, can someone post a step by step so i can go to the dealer and do it front of them or show them.

Thank you.

 

SCT programmers do wonders for your truck and also allow you to adjust for tire size changes. Your dealer is an idiot

 

Yeah i know the programmers can do it. But i dont wan't anything not approved by Ford so they dont deny my warranty if something goes wrong. I have read before that there are some settings that can be configure for different tire sizes. Just need someone with first hand knowledge to post about it.

 

Ford can get you close... My 2010 has 35's and was only off a few MPH after Ford adjusted it. but get the tuner and be done with it. You set it back to stock every time it goes to the dealer anyway. What they don't know won't hurt em. ;-) you'll love the new shift points and increased gas mileage too!

 

110% agree about the tuner's way of changing the shift points!!

 

As long as it is not an 03-04 truck the SCT tuner will do the trick, and yes return to stock before you bring it in to a dealer, and read this to know you real rights when it comes to warranty issues http://www.sema.org/sema-enews/2011/...ermarket-parts

 

True. I was assuming it was 09-11 if posted in this spot... but assuming has only done me so much good so far...

 

You only have those rights you can pay a lawyer enough to defend in arbitration or court... and Ford will bring the big guns...

Returning the truck to stock will not permanently clear the evidence of the tuner from the truck...ford maintains permenent files in the computer that record if the truck was reflashed that you cannot delete. The dealer may not look at this but if there is a serious issue the factory technician who Ford will send out before performing your repair will...

Anywho...

To the OP. The dealer is full of it and SuperDave is right. They recalibrate the speedometer by adjusting the computer for a different tire size. It recognizes what the revolutions for that size should be and it alters your speedo and makes your odometer accurate again. However there are limited sizes in the Ford computer that they can allow for and they may not have your exact size but can approximate it by diameter of the tire. Use this for determining the diameter of different sizes so that you can get as close as possible at the dealer.
http://www.miata.net/garage/tirecalc.html

 

My Ford dealer recalibrated mine. Cost me $50 while it was in for something else. I had increased the tire size and the speedo was off by roughly 10%. They just enter the new tire size and you're good to go.

 

This is what i dont get. I have read about post like you guys that they can do it.

What pisses me off, is that they changed the tires and i was quoted a price for the job and paid for it. I dont want to go to another dealer and pay again for a job they did not complete.

So i have gotten my answer somewhat, still hoping a Ford tech will pop in here and give a more detail instruction on how to change it.

Truck came with 275-65-18. I put 275-70-18.

Did not think it would be that big of deal to adjust the freaking computer.