I'm new to the Forum, so I'm sure this has already been discussed, but I'm hoping for a quick answer.
I have a 2009 1500 Crew Cab Laramie 4x4. I leveled the front and and just got new tires because the factory Wranglers were junk (that's another story). I went with BFG All Terrain in a 285/65/20. This should constitute about a 4.5% difference in my speedometer reading. So, I took it to my dealer to have them recalibrate my speedo... Now I'm 7.5% different! They said that size is not an option so they didn't know what to put in for tires size.
Can someone that actually knows what they're doing tell me what tire size I should have them input into their calibration software to get me at least close to what I should be?
Thanks for your help.

 

Personally, I would buy tuner such as a Diabloisport Predator or Superchips and do it myself.
Basically, they just need a tire size with the same OD dimension.

I would somewhere like tirerack.com and look up your tire, then just look around at other sizes that have the same OD and write them down surely the dealer will have one of the sizes that they can use.

By the way, welcome to the forum!