What is the importance of the windjammer under the stock bumper? Should I just take it off or leave it on? Does it have any importance?

 

That's an air dam. It's good for deflecting baby possums, that's about all.
Mine ripped halfway off backing up in a mudhole after having the jk a few months.

 

improves gas mileage and reduces hood flutter at high speeds.


many people take them off. I took mine off till I found out what it does, then I put it back on.


sure it's plastic, but so is the rest of the jk.

 

Ok I'll put it back on then

 

I have lots of miles both with and without, and it certainly does not stop hood dance--not even close. To argue whether it reduces it by 2 or 3 percent doesn't really matter--put Zip-ties on and be done with the issue. The same with gas mileage--if it improves gas mileage, it would be impossible to prove by anything the layman could collect--it certainly can't be over a tenth of an MPG--if even that. Pull it off--it's an ugly, useless piece of crap. If you don't pull it off and you off-road, then you will pull it off soon enough. If you leave it on, then you may as well make a giant decal that says "MALL CRAWLER" and put it on your hood, because no one who seriously off-roads would ever leave that hunk of junk in place.

BTW: It's primary purpose is to improve airflow to the radiator by creating a low pressure zone behind it. But, since no one seems to be having overheating issues after pulling it off, even those in AZ and the Middle East, it doesn't even do that job very well.

 

having it on surely helps my A/C performance.. one of the things it does is to help air 'recirculation' from the engine compartment back through the radiator....

stopped in traffic with just a bit of a breeze from the direction of the rear of the jeep will push lots of heat out and under the jeep and back up into the radiator.. makes for more likliehood of overheating and lessens A/C performance...

I took mine off because i thought it looked ugly.. but put it back on when I noticed the condensor temperatures were up higher than before and the fan was running on high speed much more often than before...

-Christopher

 

What about when you install a different bumper and you have to remove it are your temperatures higher and fans spinning faster?

 

I notice no MPG or Flutter change on mine after taking it off and I follow my MPG on every tank og gas, nor did my AC perform any different...

Take it off and forget it, like you said, new bumpers would mean the same thing.

Just my 2 cents and others may disagree...

 

I'd think it had some importance on the stock vehicle. If not, it wouldn't be there.

 

My JK is basically stock except with 33's it seems it adds clearence with it off