Grill Cover Questions

[chuntag95]

I put my grill cover on for the first time due to hitting the 20's (not a real regular occurance) and I was going on a trip. (The last cold weather trip I never got above 185 and the tranny was at 130. Mileage was not too good either.) By the time I got to my in-laws, the temp had hit 50ish according to the mirror. I watched the gauges and they were at the normal warm weather numbers and I was wondering if I was getting some waste heat to drive the up. So, the questions:
1. What is the max temp to have the upper cover only on?
2. How much damage is done with dirt under it?
3. Would one of the SS inserts like JK has on hit truck be a better solution for us souther folk?
I did like the fact that the truck heated up before the first 30 miles.
Thanks in advance for all of the info/opinions.

[Oongawah]

I sent an E-mail to John about getting those black-out plastic covers for mine. I know out here in the mountain/desert the factory one will scatch up the grille real nice like. I'm still waiting to here from JK, but he's better to catch on the phone. As far as temps goes, I leave mine on up to 60 degrees. I don't think I'll ever need the bumper cover unless I take a trip up north. Hope this helps, Chuck.

[FrozenAKJoe]

I run my grill cover when the temps get below freezing. I think I lose about a half a mile to a gallon. I also find cleaning the darn thing to be a royal pain. My engine temp never gets above 185, but then again I never tow/haul during the winter, either.

[Maverick]

Chris,
The temp sensor is behind the grill. With the grill cover on it cannot read an accurate outside temp and gets a better reading off engine bay area temps. Nothing to worry about. Some have relocated the sensor to the headlight area to get a blast of wind with or without the cover on.

[chuntag95]

Thanks for the info guys. I will look into relocating my sensor and using the cover more. It really makes a difference on warm up and from what I have read here on mileage too.

[jbplock]

On my 03 the mirror Temp sensor is accurate in the stock location as verified against an independent digital thermometer. It also remains accurate with the (upper) grille cover on - except when sitting idle I have noticed the temp reading will rise a little.

[TLA]

I relocated my sensor to the air dam. I am more worried about road surface temps (ice!!!).
I leave my cover on - just the grill - all the time right now. I even tow with it, and the things I notice are fan cutting in more, a bit higher trans temp, and a bit lower boost. Obviously, when I tow with it on, I do watch the guages like a hawk.

[chuntag95]

Relocated my temp sensor to the plastic shield below the DRL. 15/32 drill bit and it popped right in after I got the wire loose. Also found the DS fog light bracket has busted and it was just flopping around. 2 fender washers and some super glue got it back in place, but who knows how long it will last.
I am trying a little experiment. I put a couple of cardboard pieces behind the intercooler, but before the radiator. They cover about 1/2 the radiator, so I don't think they will be as good as the cover, but they also don't restrict the flow over the intercooler for the efficiency loss. I will monitor temps and see what the milege does. I saw another thread that talked about this, so I am trying it. I might go back to the cover due to the ease of pulling it due to the yo-yo weather we have here. 20 today and 80 tomorrow, you gotta love it. I have to pull the top plastic cover over the radiator (7 pop up connectors) to get them back out. I made tabs from duct tape and taped them to the support so I can get them back out.