The reason it's a good itdea to recal after if you go 10% or more on your tires is there are a bunch of things that are based off of the rotation.

1 - Obviously your speedo

2 - Your tranny will be out of synch and will hunt for gears and shift at speeds that may not be in the engines optimal power band.

3 - Your ABS reads the from the tire rotation and can react poorly if it's not calibrated.

4 - Technically, your odometer is false with the big tires.

Do you have to? No. Do you WANT to? Yes.

 

Heck with the bigger tires, I need fender flares, even with the stock tires, my truck when from white to brown in 2 minutes going up a paved road quickthat the dump trucks use after a quick rain, I had the truck and my trailer a mess.

As soon as I stepped out of the truck and I seen it at the next house, I couldn't believe how quick we got dirty on what I thought was a clean road and grabbed the one inch feed line for the water meter and scared the hell out of the dog from all that water force hitting the truck and not a bit of dirt fell off.

If anyone knows about some good flares let me know

 

Bushwhackers! Love those flares.