SIL necessary?
 

*warning* newbie here. I did a quick search and I was just wondering if the SIL on the VX necessary? I did a fueleconomy.gov search and it shows the SIL getting 4 mpg better then the none SIL option. Why the increase of FE? just because knowing the right time to shift? or is there something more to it

So I guess my main question is, do I need to make sure my VX has a SIL?

The manufacturers get a fuel economy "credit" applied to models equipped with the shift light. The credit is based on assuming people actually shift when the light tells them to.

so its just a light? and w/ or w/o the light as long as I drive it the same I should get the same FE?

Yep, its just a light...

Yea, its just a light, but it helped me to the tune of about 3mpg when I started paying attention to it.

And that's why the manufacturers get a FE credit for putting the light in the cars. I think the EPA tests require shifting when indicated in calculating the EPA estimates.

-Jay