Andre`

I have 37" BFG`s on a Rubicon. After fitting 5.38 ratios the computer shows very high fuel consumption. It does not feel like it- smaller gas pedal opening. I have re-calibrated with a Procal. I am busy checking actual consumption. Could it be a problem with the computer?

tpm152

Gas pedal opening does not have as much to do with fuel consumption as many think. The engine RPM has much more to do with the fuel consumption than the pedal position. For instance with the 6-speed my JK has -almost- no difference in fuel economy when I leave it in 6th gear at the same speed with 10% throttle versus wide open (100%) throttle.

With an automatic the pedal position does have some relation to the engine RPM (thus fuel consumption) because at high throttle positions usually the automatics will downshift (increasing engine RPMs at a given speed). But if your average engine RPM after the regear is higher, then I would not say it is likely that your fuel consumption has also increased.

Andre`

It is due for a service and has been booked. I was just shocked as everyone on the forum claims better fuel economy after regearing. I know it will be worse on a level road as the rpm is 500 higher. I do live in a very hilly area.

Andre`

I don`t think it will get any better. I have filled the tank and reset the computer. The speed limit in South Africa is 75mph and if you drive any slower everyone will drive you off the road. My foot has become much lighter on the gas pedal.