If your seeing 3 tenths with 3.73's, imagine what you would see with a 4.10 gear. And it won't hurt your fuel economy, I run 4.10's in my 96 SVT Cobra which is heavily modded and still see 21mpg. in the city. On the highway, it's around the same as long as I keep my foot out of it. If your planning a gear swap, I would go with 4.10's over 3.73's or even 3.90's, Mike. SCT Tuner.:bigthumbsup