I've noticed little or no change in gas mileage. I've had 4.10s in my 03 Mach 1 for about six months and use it as a daily driver, as well as recently having taken it on a 2500 mile road trip. Remember the wise words "don't fear the gear". It costs the same to put 3.73s or 3.55s in as it does to put in 4.10s.

 

yep. look for jd's post about his highway driving with 4.10s. he got some nice mileage!

 

Yea i haven't heard much about the TLOK