Hey guys. Ordered my H2 rims and tires. Going to the typical 315/70/r17's

This is a pretty big step up from the stock 265's so i calleed dodge to see about recalabration the speedo to the correct size. They tols me they can do it up to a couple sizes larger then stock but not to the diameter of the 315's bummer.

Well got to loking around and found this, Speedometer Recalibration Device.

Its from 4 wheel parts. Anyone ever tried one?

Im sure there are others out there that do the same thing.
For my 03 2500, its $220.

Think i might give a shot.

This works for from 22.5 inch to 44 inch tires from what i can see. Also recals for aftermarket rear ends too FYI.

 

 

Get an edge you can recalibrate the speedo and get some performance too lol but it only reads the right speed on the edge guage.

 

If you are indeed driving a 2003 then they can recalibrate your truck for 315s. I did it on my old 2003 with the same rims/tires. You need to know the number of revolutions per mile for your tire (You can find it at tirerack.com) and tell the dealer that you need your pinion factor reset to that number of RPMs. It is amazing that some dealers still don't understand this! I even had a dealer tell me they could not do it because they didn't have a dyno for it!! It takes the tech about 10-15 minutes. Some dealers do it for free and some charge a half hour or even a full hour for this small service...
The TruSpeed thing works too but it costs more...

 

Another option.....Smarty JR.....I just ordered mine today and can't wait.

Also, Dodge should be able to adjust 2003-2005 trucks for any tire size from what I know.

Have a good one.

 

Get a SMARTY bud, it will do what you need, and you will love it, I guarantee it, look at my sig, I went from 265's straight to 37'' tires

 

There's an S06 in the classifieds for $600. It does all that you mentioned AND will help you expedite the choice of your next tire purchase.....................and tranny......................and exhaust..........................and injectors......................and turbo......................and??????????????????

 

An old Snap-On Brick Scanner will do the job too. Almost any auto repair shop has one of those lying around.

 

The only reason im looking into this option is because my buddy has an 08 and this unit has the same part number for both trucks.

I've heard of the pinion option from the dealer. I think im gonns look into this. Will that work with the 6.7 08 too ?!

 

I`ve got the Super Lift Tru-Speed on mine...works great , and is adjustable to any tire size and also has 2 settings , in case you ever run 2 different sets of tires that are different sizes,

 

2006+ trucks can only be recalibrated up to 285's at the dealer, same size the power wagon is running. A smarty will recalibrate it for anysize you want, something even the dealer can't do.

FYI, you can have the dealer can mess with pinion options in their scan tool, if you have 3.73's and tell it you have 3.55's and 285's, it will change your overall gearing in the computer and put you closer to your actual speed.