I was curious to the difference in MPG with the top up vs down or any other configuration like Sunrider.
I got my 08 X right at the end of summer and didn't get enough play time during the warmer season.

 

I doubt if it would make much of a difference. No matter what, JKs have terrible aerodynamics.

 

i know when my tops and doors are off i get horrendous gas mileage. about 10-11mpg




-shaun h

 

With the hardtop on and summer fuel I could consistently crack 20mpg. Last summer I took the hardtop off completely (and left it off) and I was consistently running about 18.5mpg.

 

I think the best is top up, second best is top all the way down, and worst is with the sunrider top back.

 

I have dual tops, and thought that I was getting better mileage with the softtop on (and up), but I think it's mostly the season/temperature/fuel.

 

top off doors off, etc. is the worst. top up doors on is best. the difference is maybe 1-2 mpg from best to worst. Not enough worry about.

 

I figured the Sunrider would be the worst, just didn't know if anybody else actually knew.
I appreciate the input guys.

 

Naked or dressed the difference is very little.

 

Swirling air is the enemy in this case; swirling air causes drag, which literally slows you down at the same power usage, or consequently causes you to use more power to go the same speed. The more you disturb the air (especially as it tries to get back together after you've gone through it) the worse the effect.

Look at an airplane wing... sorta blunt at the front and gradually tapered to a point at the back... this allows the wing to go through the air with a minimum of disturbance.

With the top on, most of the swirling happens at the back of the vehicle, the square shape of which you are largely stuck with. (Adding an air-smoothing fish-body fairing would just be WRONG). The fenders, mirrors, etc are the same - top on or off. Anything in the wind causes swirling drag...

With the top off, you get the air hitting all manner of things to cause swirling: sportbars, padding, seats, hats, sound bar, junk in the trunk, passengers, dogs, seatbelts, spare tire, hi-lift jack, cooler racks - EVERYTHING.

There ya go - more than you ever wanted to know.