Speedo Gear Impacting Mileage

[BCB75]

Why specify non-Rubicon when talking about speedo gears? Is the Rubicon set up different? Curious as mine has 33s now with no other mods and was wondering if my speedo and mileage counts were correct.

 

[Viking Jeeper]

Why specify non-Rubicon when talking about speedo gears? Is the Rubicon set up different? Curious as mine has 33s now with no other mods and was wondering if my speedo and mileage counts were correct.

Yes, Rubicon is set up differently. The speedo gets its signal from the transfer case and Rubis have a different transfer case. Non-rubicon speedometer can be fixed with a gear of different size. As far as I know the only way to correct the speed in a Rubicon is by intercepting and modifying the electronic signal sent to the speedo (or PCM, I dont know).

 

[Ephry73]

One thing to note is advertised tire size, versus actual size. Just to make sure the calculations are correct.