[Bob T]

I had my 2014 JGC reflashed May 31. Since then I have noticed a slight decrease in performance, starting from a complete stop. The most change has been in getting poorer mileage. In town has decreased from 22-23 to 17. Highway has dropped from 29-31 to 24. I also had to return to the dealer to get my check engine light reset a few days after the reflash. Has anyone else suffered this mileage drop?

 

[pinelureTT]

Transmission is down shifting from 8th gear to 7th more often now.

 

[cmvet]

So far, after 600 miles, I'm averaging 27.5 mpg with mix hwy/city driving. I had the AEM update on Nov 1 (with complications). I currently have all-terrain tires and the mileage is the same pre and post AEM update. When I had the forterra tires on there I averaged 29 mpg. Acceleration lag is my biggest issue following AEM.