Lift question

[UofMF250]

I plan on lifting the truck here in the next couple weeks and had a few quick questions. Im running H&S and noticed at the beginning of the install there is an option for tire size recal, do i have to do a whole new tuning process or is there a way I can just change that one option? Also when it changes the tire size, is this going to recal MY spedo or just read correctly on the H&S? If not is there a way to make my spedo right?

[6GunFighter]

U,

1. Best way to calibrate tire size with the H&S put on your tire put to operating pressure and measure from the center cap to the ground on the rear wheel and divide it by two..

2. I am running 296/65/20 nitto's and mine was within 2-3 miles slow of the stock speedo from 0-120 Mph but no way to adjust the stock speedo itself but I cross checked it with a GPS. And you can also monitor speed on the black maxx itself...

3. And yes you can only set the tire size calibration on the beginning of the tune it doesn't take long to reinstall also have to do the tpms delete if you have it at that time too hope this helps...Steve

P.S if you have an Iphone the dashboard app is pretty spot on with the GPS cross check and free

[UofMF250]

thats what I wanted to know! thanks Steve, though not what I wanted to hear! haha


PS I use Droid

[6GunFighter]

Originally Posted by UofMF250

thats what I wanted to know! thanks Steve, though not what I wanted to hear! haha


PS I use Droid

You welcome!!!!! But droid = NERD lol j/k

How big tire rim setup you wanting to run???

[UofMF250]

haha

Im just going to a 35/12.5/20

so nothing fancy, and it shouldnt change the spedo that much (or the mpgs) but I was just curious.

[6GunFighter]

Should be pretty darn close to 2-3 mph slow if your stock speedo was calibrated on 20's if it was on 18's I am not sure the difference..Steve

[p8ntballn2]

the diameter of the wheel should not affect the speedo at all.. it should be the overall diameter or circumference of the tires.. if you think about it, say you're going to travel 1 mile, the bigger your tire is.. the less revolutions it has to take to carry you that 1 mile vs a tire that is smaller.. thus affecting your speedo and odometer.. you could have a 35" tire with 12" wheels and it should be the same number of overall revolutions as a 35" tires with 20" wheels..

[TripleE44]

The dealer can re-calibrate your speedo up to 35'' tall tires.

[6GunFighter]

Originally Posted by p8ntballn2

the diameter of the wheel should not affect the speedo at all.. it should be the overall diameter or circumference of the tires.. if you think about it, say you're going to travel 1 mile, the bigger your tire is.. the less revolutions it has to take to carry you that 1 mile vs a tire that is smaller.. thus affecting your speedo and odometer.. you could have a 35" tire with 12" wheels and it should be the same number of overall revolutions as a 35" tires with 20" wheels..

Correct!!! But say he had stock 18's that were 33's and that's what the stock speedo was calibrated at that was the assumption. It would differ from going to 35's on 20's was the point I was making but only by circumference. I am unsure of what exactly he is running but I know you can set it to what ever tire size with H&S tunner you like but it will not override the stock speedo setting it will only show you the difference your slow or fast...Steve

[Jonnydime]

My Mini Maxx adjusted the speedo on my truck it was reading 3 mph fast before and now it reads 1 mph slow after I adjusted the tire size.