On some cars there is a plastic mold that covers the underside of the engine, usually for two reasons - protection and aerodynamics. Does anyone know if there is aftermarket part for this since there is no oem option?

Search "belly pan" on Ecomodder.com (all DIY). As to aero, it appears that open screen material may serve the same purpose.

Coroplast is the material of choice for inexpensive DIY (to see what works), and there are several excellent threads on the subject (the gains are real).

http://ecomodder.com/forum/showthrea...cks-15230.html

If my understanding is correct one can "seal off" the area underneath (from the front wheels back) from body outer edge to frame-rail for a benefit. (Parallel to ground or chassis)

Side skirts are also of benefit; again, if my understanding is correct, keeping air from crossing underneath vehicle promotes "clean" aero. (Extending downward from body edge towards ground).

On the front end extend the air dam down some to channel air "around". (I've made measurements of truck air dams in a parking lot and found none -- stock -- lower than 7" clearance). On my stock 2WD the air dam has 10" clearance. Somewhere over there I have seen the comment that front air dams need (given a stock height car, say) only channel air away from front end components (spoiler on front axle). Etc.

http://ecomodder.com/forum/showthrea...ckup-3171.html

A comment by Big Dave is (roughly): "Every time I improve aero I can tell by how much quieter it becomes" (FORD SuperDuty 7.3 averaging above 25-mpg, all miles).

For a pickup the best, first, aero improvement is the bed. A tonneau cover, a close-fitting cap (Aerolid), or DIY of same (great threads on this).

As a grille block is problematic on a diesel, then it may be that a MOPAR Winter Front can be used for some "aero" qualities along with some applied-to-the-front-of-the-grille-mesh "winter covers" (Cloud Rider and others; or, DIY from Lexan). I'd try the outer (upper) cover first.

If the questions concern N-V-H (Noise-Vibration-Harmonics), then investigate the TSB on door seals for some years of 3rd Gen (and/or adjust door striker), plus:

http://www.carsondodge.com/forums/showthread.php?t=67

http://www.fluidampr.com/CUMMINS.htm

http://www.balancemasters.com/driveshafts/index.html

http://www.dieseltruckresource.com/d...0&postcount=13

http://www.atpwrap.com/html/dodgeram.html

http://www.dieseltruckresource.com/d....html?t=145241

Tire tread design is the biggest NVH problem to solve. And adjust pressure according to Load Range Tire Chart to exactly meet scaled weight (neither over nor under Chrysler specs). Plus brake rattles and other loose componentry.

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So who sells the Belly Pan for our trucks?

D-I-Y, Inc.

Is it about aero for mileage, or for sound?

Sound. I'll modify it if need be, if possible.

Ok...was that a joke that went over my head? DIY=Do It Yourself, or is that a real company? LOL!

I tried googling it...couldn't find jack!

Just don't forget, that with even a little room, snow will get in them and can pack it tight, creating more problems than you solved. Possibly in Canada you don't see snow however!

You're right. Gotta watch how I park it in my igloo!

No, I had a sports car I drove in winter. Had a belly pan. No problems.

We do have something called a "r-o-a-d p-l-o-w".

You should Google it.

When I used to work on over the road trucks, I saw some issues with snow packing tight in the frames and around side skirts and fairings. It was from the powder that they kicked up going down the road. Some of them would not thaw unless left in over nite.

I have a heated garage... I mean igloo!

Yeah, I was pulling your leg about DIY, Inc. (There probably is some company out there with such a name). If you'll read up -- and post your questions on Ecomodder -- about belly pans, etc, for trucks you might find responses smarter than mine. I have seen at least one reference to using a screen material (think expanded metal) as the air flow is about the same as with a non-pervious material.

But this may not render appropriate sound reduction. Ask, as someone may have already tried it (weirder things have . . . . )

I would think ATP, Inc for drivetrain noise stuff, and looking at the wheelwells for much of the road noise problem would be good once past tires.

The FORD guys have a thread out there about using silicone surgical tubing to beef the innards of weatherstripping to cut wind noise. And there's a DODGE TSB on the same subject.

Most of all, don't think that all problems are hearing related. Noise-Vibration-Harmonics are inter-related. I've been in vehicles that tested louder but didn't seem like it as the vibrations were much lower than a similar vehicle.

Why not try automatic wheel and driveshaft balancers, and have your shop loosen up the motor mounts to have it re-settle (and the rest of the Carson Dodge link rec's). Then door/window seals. That's where I'd start.

Let us know what you find; keep this thread going!

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