Anything to help direct water away from the alternator and the fan blade is a plus. Only takes on good mud hole, to make a believer out of you. If the fan blade catches the mud, it will pile it up on the top of the motor fast.
I took mine off and I have been fine. The way I look at it is, you can always wash your engine off and your air filter is almost at the bottom of your engine bay. So if you go higher then that rubber stuff, you will be sucking in water.
If it isn´t trashed past the point of saving, I´d use some cable ties and whatever to hang it back up there. Only takes one time, I´ve seen motors with a hundred pounds of mud on the top of the motor. Makes trying to find what made your motor crap out, just that much harder.
Mud and water are good reasons, but I also think it might aid in airflow. with the cover across most of the bottom, the airflow is directed over more of the engine compartment. When idling, you might aso avoid having the fan pull air into the radiator that just came out from under the Jeep.
i took it off, no problems as of yet. I liked teh look without it better, gives the front a beefier look. But at the time i coulnt find a reason to keep it. and now that i have heard a couple maybe i should of thought twice before using tree pruners to cut it off. :looney:
probably called a splash guard or sheild...
i repaired mine by cutting out 2" circles out of an old inner tube, then glued them to the original (torn) mounting holes on the guard, on the top and bottom, poked new holes in the rubber and bought some new press-in tabs at lowes, now its as good as new!!!
I wouldnt recommend taking it off. One of my friends with w YJ took his off for no reason only to have mud and rocks fly up and break 3 spark plug wires and soak his distributer while going through a mud hole. Just punch some new holes and throw some zip ties on, it was put there for a good reason.
Amen to all the "keep the shield" advice. If you watch this forum regularly, about once a month some poor soul shows up with a tale of woe about sending his alternator to the great rebuilder in the sky because he packed it with mud because of the absense of this shield. BTW. the one they used at the factory on 99's was made out of some sort of cheesy felt stuff that would rot away over time. The replacement from the dealer is a much better quality fiber reinforced rubber.