I opted for 4.88s on my tacoma (regular cab, 2.7l) due to the extra weight of the exo cage, RTT, armor and all the other shi-stuffs. Lots of folks told me that was too low, but I love the combination. I've got almost 35k miles on the combination and my fuel mileage actually was unchanged. I've run both 285 and 265. I can tell you that the change from 4.10 to 4.88 was a great decision for me.