I still have the stock air dam (the big chuck of plastic below the front bumper) and the mud flap that attaches to the unibody frame rails below the engine but above the suspension stuff.

My understanding of the purpose of the air dam is to push the air that is hitting the nose of the jeep as it's going down the road. It pushes the air closer to the ground and away from the underside of the vehicles. This is supposed to do two things: 1) increase aerodynamics and therefore MPG by directing the air away from the non-aerodynamic underbelly of the jeep, and 2) create a low-pressure zone directly under the motor which will have the effect of drawing more air through the radiator and help with cooling the engine.

But if the mud flap is in place then wouldn't point #2 from above be rendered null?

Should I remove the mud flap? I need as much help cooling the motor as possible especially going down the freeway.

 

The air dam helps direct air up into the radiator. My Mustang has one, as do most newer vehicles, and that is its intended purpose. it is a cooling aid. Not sure about the mudflap (or splash gaurd, whatever its called). I always assumed it was to keep the alternator dry when hitting a water puddle and not much else? One of the best ways to keep the heat down is to install hood vents. but be careful with them as the TPS is usually just below, and does not like to get wet.

So how hot is it running? Normal operating temp is 210. Running the a/c will raise that some. The aux fan kicks on at about 217- 218 or so, i think? Towing, hilly terrain, ambient temp, and a less than perfect cooling sytem, obviously, will hurt it. When was the cooling system last serviced?

 

But how does it direct the air through the radiator??

It's a long story so I'll just point you to my thread all about it here: https://www.cherokeeforum.com/f2/ove...-could-236023/

 

Bump. Anyone? Remove the mud flap/splash gaurd or not? Looking for maximum air flow through the radiator when going down highway

 

I don't know a lot about this stuff. But I did just remove the splash guard (mud flap) from my vehicle in preparation for installing a new one before next winter. I also run real-time data on the vehicle displayed on a digital dashboard. I can say that the engine coolant temps have been just slightly warmer with the splash guard off. I don't have a great theory as to why, but my guess would be that without it the air escapes through the lower pressure zone before crossing over the motor. The splash guard probably force more air over the motor where it then escapes over the back section of the splash guard, taking more heat with it.

 

But to be clear, the temps were within reasonable range either way. So on or off is your choice. I wouldn't be without one in the northeast because of all the salt though. Its bad enough the damage it does to my suspension and floors, and body. But the engine compartment has remained very clean because of the splash guard.

 

Good point, I live in PA and thought the salt was bad here until yesterday, I saw a late model Tacoma from Vermont. Holy cow, that thing was a rust bucket.

 

Since installing my front skid plate [and cutting back some of the splash guard] on my xj 1994, my temps have fallen. Still looking at putting some hood spacers on for this summer; don't like the look but less permanent than installing vents.

 

for some reason I think that's just how they get haha. Where im at that isn't an issue, but man practically every Tacoma I see is rusted to **** haha.

 

Like this? not a Tacoma. Same idea though.

 

Yes sir. Not as bad since, again not in a big rust area, but those rear fenders seem to be a huge issue on tacomas

 

Excellent, thank you!