I have a 2006 4.6L with K&N air intake, Magnaflow Single exhaust. I installed the eef2400 and so far I think it runs pretty good on level 2. My question is when I turned it on for the first time to set it with custom options I made the change for the Tire size 295/70/17 = 2654, then I noticed the gear ratio was 3:55. I thought my truck was 3:73 (how do I tell) and if it is 3:73 will it hurt somthing on my truck if I set it to 3:55. It seems to get better MPG and better shifting while having it set to 3:55. I am not sure on what to do, any ideas on this. Thanks Brian

 

The tire size and gear ratio only control your speedometer and odometer. You need to enter the gears that are actually in your truck. It pops up with a default and if you have something other what it shows, you should change it.

 

Okay, I was not sure because I saw the two different values two different times. So if go back into level 2 setup and look at the ratio to verify the setting but not change anything will it reset all my settings?