The lower air deflector/radiator mount for my 2003 Olds Silhouette broke. That is, the air deflector broke off. It’s a plastic part that mounts to the radiator mount; not the mount itself. I can buy it on line for about $110 delivered, but I’m not sure I need to replace it. There are about 5 bolts holding it in place. It looks like a real easy job. I guess it is supposed to keep the front end down, but it doesn’t look like it does much in that respect. What do you think?
IMO, if you don’t want to replace it (for looks, or whatever), then for now, I wouldn’t. I would, however, keep an eye on the engine temperature (you know, just for a while) to see if the change in airflow affects the cooling at all, and maybe hit the highway and see if it has an impact on high speed handling.
Can’t think of anything else those do…apart from telling people when they hit the curb so they can stop. 
Edit: wow…only 10 minutes. I should have let someone else step in first.
I don;t think it will have much effect on the radiator temperature. The deflector barely juts below the bumper, and there is a lot of air through the grille. We’ll keep an eye on the temperature, though. Thanks for the suggestions, Chase.
As long as the engine temperature and the “feel” on the highway are fine, just leave it off. They can affect airflow, but they’re as much about style as function.
The deflector is actually pretty important as to airflow through the radiator. With warmer weather here and summer not yet in full swing you really should replaced it.
The deflector will have very little to do with engine temps around town but on the highway an engine can easily overheat if the deflector is missing. These things can make a 30 degrees or more differerence in the engine temps.
I would replace it. Assume that if GM went through the extra expense to put it in there then it is needed (as ok4450 outlined well).
However, there is no need to go paying $110 for a new one. If you have the old one, just look into figuring a way to hold it together. You’d probably want to front surface in terms of keeping its contour/shape.
Or just find one at a salvage yard. I’d be surprised if you couldn’t come in under $20 or so. FYI: Silhouette = Chevy Venture = Pontiac Montana. If you can’t find one at a local salvage yard, I have found the following to be a great website: http://car-part.com/
That air deflector below the radiator is there for aerodynamics. At higher speeds it forces the air downward so it passes under the engine smoothly. Without it, the air will be turbulant at the engine creating drag. So it’s actually a fuel saving component.
Tester
My youngest son went through this same thing some years ago on his old 3rd generation Camaro while a college student.
He came home for the 4th of July cookout and mentioned that his car had been overheating but only while on the open road. We’re talking 220 degrees plus.
I took it down the road a ways and sure enough it was pegging out pretty quickly.
Coolant level full, thermostat open, cooling fan operative, etc all normal.
He then mentioned running over a dead animal on the road several weeks earlier but assumed there was no damage.
A quick look showed the airdam was completely missing.
Just for the heck of it I called the local Chevy dealer and they priced a new from GM airdam out at 37 dollars, tax and all. Cheap enough in my estimation.
Anyhoo, stuck the new airdam on there and the highway operating temperature dropped back to under 200 degrees even on a 110 degree day.
It would seem to me with a little digging you can find the part for less than 110 dollars. Salvage yard, eBay, etc?
Thanks, guys. I’ll look for a used one first, then go for the new one if I can’t find a used unit. BTW, I can’t rebond the old air foil to the existing radiator mount. We had it on the highway last weekend for over 1000 miles and it didn’t overheat. It was no doubt in the process of breaking over that trip.