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
I have heard 3.73's will get you about .3 faster whereas 4.10's will get you .5 faster with maybe 1 less mpg. If your interersted in buying a complete set of brand new in the box 4.10 gears, frpp traction-lok, and the Master bearing kit which is necesary for the installation, go to ebay and search "mustang v6 4.10 gears bearing" Right now they are selling for about 100 dollars less than on American Muscle.com. The auction ends Sunday. Goodluck!
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