Some of them are missing the air dam under the bumper and some are not even though it is not detachable. Most I've seen do have the air dam. Is there 2 OEM versions, 1 that has it and one that doesn't? Can someone from a dealer confirm this? Do 06 models not have that?

The air dam is detachable on 04 coupes and possibly 03 and higher years but on my 05 sedan it's part of the bumper.

 

I have an '06 6MT, and my front bumper has the air dam.

 

air dam is only on awd to get air to the front diff...did u buy ur car used cuz the rwd dont have that air damn

 

I think he means the small little lip at the bottom of the bumper. More like a deflector or something.

 

When you say air dam do you mean the little black piece underneath the bumper? I have an 05 and mine came with it, I also have a friend with an 06 whose car came with one as well.

 

So THAT'S what the vent under the license plate is for on the AWD models. Never knew this.

 

Lol @ the pissed off cartoon

 

I debate that's its function is cooling for the differential. The differential is sorta offset to the passenger side, so the vent on that side would flow into it.

Directly behind the center vent is the lower radiator mount which is solid...so not really sure where the airflow is supposed to go.

But that's off topic

 

if ur talking about the little black peice under the bumper my 05x had it but the previous owner broke it off from those concrete parking bumper things

 

Yep, I have it on my 05 X.

Always wondered what it was for, thought it was some sort of a rubber weather strip to protect the bumper from scratching on parking blocks.. haha.

But yeah it is shredded a bit from the blocks...

 

Yep its attached to my bumper.

I think its an areo improvement. Nothing else it could be for really.

 

It turns out the bumpers that do not have the lip under the bumper are cheap piece of **** aftermarket bumpers and are not OEM bumpers. Good sign for anyone looking at an 03-06 that doesn't have the lip that the car might have been hit. I saw 2 at 1 local dealer not long ago.
It deflects air away from under the tires and off to the sides and that's were the side skirts come in IF the front wheels are not pocking out because of aggressive offset.

 

^^ Whaaaaaaaaaaaaaat, really how did you find this out?!?

 

I just noticed that on mine after reading this! I've had a lip in my bumper for a long time. Now that I removed it I know what you are talking about.

 

It's there to act as a splitter and conditioner for the air traveling under the car. The splitter function is part of the zero lift that Nissan engineered into the car (assuming rear spoiler and rear wheel diffusers). The piece keeps air flowing underneath all of the uneven surfaces below the car (i.e. exhaust system), instead of through it. This is good for fuel efficiency. It does deflect air from the tires but if that were the only purpose, the strip would only be in front of the tires (as it is for the rear tire diffusers)--this can be seen on IS300's.