hello i just helped my dad replace his stock 17" steel wheel with 265\75 tire. we put on some 275\60 with factory 20" rims on. will it throw the speedo off much to worry about it? if so is there something easy that i can do to change it.

 

The 20" tire is .4" taller than the 17". That would make it 1.0% faster or when driving say 60 mph,you would actually be going 60.6 mph. What to do? You might be able to get the computer flashed for that size tire. I would just go on my way. It is not off that much of a difference. Hope this helps.

 

actually, it wont throw them off if you keep the tire diameter the same. As long as you keep the wheel diameter the same then it wont throw anything off. Though, theoretically thats what should happen but the added weight of the 20' rims may throw things off but I dunno.

 

Yup, keep the diameter the same, or very very close, and it won't affect the speedo, if you're looking for factory oem refinished wheels, check out <snip>

<link removed> - Commercial posting without sponsorship is not allowed per DodgeForum rules.

 

i have wheels already thanks. i say things are off a little. side by side the s with tires where about 2" taller then the 17"s. i think my dad asked the deal and they said they would do something to fix it. i was just curious what they would do for it. my buddy has one that did the same thing said his speedo was off about 2mph is all. but he has a 50 series tire too.

 

why not just fork over $300 to buy a Superchips and then use that to recalibrate the speedo as well as get some serious performance out the truck.......doesnt sound bad to me. [sm=goodidea.gif]

 

The SUPERCHIPS is the way to go... I have had several differenct tires sizes on my truck and when I had the superchips I was able to adjust for the tire hight in just a few seconds,

IF you are NOT in the market for the SC then you could just go to the dealership and ask them to adjust the PINION FACTOR... they will input your rear gear info AND tire hight and correct your speedo...

Most will set y our pinion factor for free... but I have seen a few stealerships charge up to 80 bucks for the service.

If you are in the market for a SUPERCHIPS contact me... I may know where you can get one DIRT CHEAP!

SPEED SAFE, AIR RAM

 

Wheel weight has nothing to do with it.

 

Where is this SUPERCHIPS for dirt cheap?? Do they make one for an 04 yet???

 

No not yet for the 2004 4.7L... but the do have the 3715 Micro tuner for the 2002-2003 4.7L and the 3815 FlashPaq 2003-2006 HEMI...

A few people already have the heads up on the "DIRT CHEAP" prices... I will let them give you the details.

SPEED SAFE, AIR RAM