I've looked through the forum and FAQ section and unable to find a definitive answer. Went with 33s and 4.56 gears...Is there a speedometer calibration device that will work for the 2004 Dakota 4.7L? I tried Hypertech and it does NOT work.

Any assistance much appreciated!

 

The speedo comes off the rear axle, so gear change does nothing. Speedometer requires a device able to access the ABS computer (DRB3, MT2500, or similar), and is entered as tire revolutions per mile.

 

Ok, so best advice so far imo: Spend the $100 and take to the Dodge dealership for speedo recalibration!

 

That or if you have a scanner that reset the pinion factor. Check with autozone and if they have a scanner that can change the settings.

 

Thanks for the helpful info.
Btw, went with the dealership option but I'm still 1.5 to 2 mph off according to the GPS and speedo apps. Oh well, close enough

 

Do you know what revs/mile number they used? You should have supplied the one form your tire manufacturer.