Air Dam Removal MPG Hit
10-10-2011, 06:03 AM
#1
JK Super Freak
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Air Dam Removal MPG Hit
Hi all,
Just curious what others have seen. When I first put my 35s on I just trimmed the air dam so they would fit. After reading many say that it didn't really do anything anyway except MAYBE save help with MPG, I decided to rip mine off - it looks better too. I figured that my MPG drop from 15ish to 13.5 max must have been from putting the hard top back on, but after an especially warm weekend this weekend running no doors or top, the MPG still stayed around the same, only creeping up to 13.8 max. It's gotta be the air dam right? I've run every variable before - doors, no doors, hard, soft top, etc, and always could keep it up around 14.5-15. I'm putting it back on next weekend!
Anyone else notice a similar hit?
Just curious what others have seen. When I first put my 35s on I just trimmed the air dam so they would fit. After reading many say that it didn't really do anything anyway except MAYBE save help with MPG, I decided to rip mine off - it looks better too. I figured that my MPG drop from 15ish to 13.5 max must have been from putting the hard top back on, but after an especially warm weekend this weekend running no doors or top, the MPG still stayed around the same, only creeping up to 13.8 max. It's gotta be the air dam right? I've run every variable before - doors, no doors, hard, soft top, etc, and always could keep it up around 14.5-15. I'm putting it back on next weekend!
Anyone else notice a similar hit?
10-10-2011, 06:13 AM
#2
JK Jedi Master
I've been saying for years the air dam's purpose is to route air more cleanly past the front axle, and to lower the pressure in the engine bay, (promoting air flow through the radiator).
There is anecdotal evidence on both sides of the argument as to whether or not having it on makes any difference.
There is anecdotal evidence on both sides of the argument as to whether or not having it on makes any difference.
10-10-2011, 06:16 AM
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JK Freak
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Yea the airdam does make a difference in mpg. Mine is stock but a winch/bumper and no airdam, I lost ~1mpg by losing it. So on 35's I can see you losing even more.
Around town though it's not overly noticeable, but highway is where I see the loss.
Around town though it's not overly noticeable, but highway is where I see the loss.
10-10-2011, 06:41 AM
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JK Super Freak
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Air dam is ugly.. Leave it off. 
Or- if u feel it helps ur mpg, perhaps gettin a better aftermarket one like the skidrow one from the quadratec mag.
Or- if u feel it helps ur mpg, perhaps gettin a better aftermarket one like the skidrow one from the quadratec mag.
Last edited by SaFFFari; 10-10-2011 at 06:44 AM.
10-10-2011, 07:44 AM
#5
JK Super Freak
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Checked at the pump and did not see any difference. I ran for a week with and without, both times driving to work keeping the routine the same. Filling up at the same pump both times the mileage was the same rounding up. If you plan on taking it off road, and I don't mean fire roads then you will most likely damage it or leave it on the trail.
Thats been my experience with that big plastic thing.
Thats been my experience with that big plastic thing.
10-10-2011, 07:50 AM
#6
JK Enthusiast
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Funny how so many people continue to refer to that air dam as a skid plate. I've had mine on and off on both the 2011 and 2012 and figure it's a solid 1 mpg immediate impact - downward.
10-11-2011, 09:54 PM
#7
JK Super Freak
Wellll, I took the plasticrap off and left it off - but put a steel skid plate in the same place.
On the trail it offers up some protection for the steering.
On the highway it adds some MPG and keeps the hood from flapping when trucks go by.
On the trail it offers up some protection for the steering.
On the highway it adds some MPG and keeps the hood from flapping when trucks go by.
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10-11-2011, 10:21 PM
#8
JK Super Freak
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but not the weight of a winch and bumper
lol sry had too
10-12-2011, 04:11 AM
#9
JK Super Freak
I noticed a loss of .5 to 1 mpg when I took the air dam off. But i added a PureJeep bumper that weighed a fair amount more than the Mopar Offroad I replaced.
So it is hard for me tell if the mpg loss was from weight or the air dam.
Probably both.
So it is hard for me tell if the mpg loss was from weight or the air dam.
Probably both.
10-12-2011, 05:59 AM
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Considering others without a winch/steel bumper are seeing the same thing...yea.
Weight and Aerodynamics are two different things. Not that the added weight won't make a difference, but in this case it's pretty negligble. (with what I've removed we're talking ~50 pounds added max onto a vehicle already exceeding 4000 lbs)
Weight and Aerodynamics are two different things. Not that the added weight won't make a difference, but in this case it's pretty negligble. (with what I've removed we're talking ~50 pounds added max onto a vehicle already exceeding 4000 lbs)
Last edited by Steelgrave; 10-12-2011 at 06:00 AM. Reason: I cn't spel