with the edge the tire sizing says to go in small steps and over time soo what are the steps that should be taken and what are to large of jumps im trying to go from stockers to 34.80


also will changing the tire size fix the dash speedo??

thanks matt

 

I would cut it in half, if going from a 31 to a 35 I would set it first at 33 and then to 35, you are adjusting the tire size in the Edge to correct the factory speedometer and odometer, so yes.

 

I just replaced my stock 275/65R18 on my FX4 to a much bigger 35/13.5R20.

I didn't have any problem setting it to the correct wheel size with the EDGE. At 35" the EDGE size is 2792mm.

Yes, the EDGE reprograms the PCM and changes the speedometer to the corrected speed for the new tires.

Schmidtty

 

That will get you close, but if you want to be as accurate as possible, don't rely on the manufacturer's spec'd size. Chalk your tire and mark your driveway so you can measure one full revolution. (Do it a few times, to be sure) This gives you an accurate circumference and accounts for the 3-5% "squish" where the tire is knocked out of round.

1" = 25.4mm

 

What should I change my edge to in mm if my setup is 305/50/20? And should I jump straight to that or gradually step up?

 

The "small steps" don't really apply to tire size. Right is right.

Use the method I described above to figure the size. Do it three times and take the average if they're all close.

 

Why?