Extended air dam...
 

Gonna see how much this will improve my mpg at around 70mph on my trip out to California this weekend. I had to make sure to add in a slot fer the transmission cooler. I only saw about 1mpg gain on my trip from Texas to Kansas.

Original air dam was 6" from the bumper. I dropped it down 5" more and added some coroplast over it.

Dropped air dam...5" from the stock position
https://www.fuelly.com/attachments/fo...a2f9121a37.jpg

Coroplast over the dropped air dam...about 8.5" clearance from the ground
https://www.fuelly.com/attachments/fo...64f8bc0936.jpg

Current extended air dam...about 1.5" clearance from the ground
https://www.fuelly.com/attachments/fo...db973d4fff.jpg

Hopefully you do not scratch it up too bad. Have mine at lowest 5 1/4" off ground. Looks as though it will be very effective.

Joel

Wow! That's an air dam! I'm very very interested in what you get, as this is the first of my planned tests, as well. Keep us posted!

Wow that's low to the ground. However, it looks like you'll be pushing a lot of air out of the way with it. You may want to consider putting an angle on it part way down, that way it wouldn't have to push as much air out of the way, and more of it would flow under your truck. Let us know how it turns out! I am curious.

What are you using to space out the OEM piece from the bumper?

I got some 1/4-20 thread-all, 12" and cut them in half. Used some T-nuts and flattened the spikes out and put that at the bottom. Used some poly tubing from Home Depot that I cut to 5" lengths. Bolted it all up together with washers in between the tubing and the bumper/air dam and nuts on top of the bumper. I realized I could've used the same sort of nut clip that Toyota had on the air dam but in a 1/4-20 AFTER I went to Autozone. No matter...it's working just fine. Thinking about adding some 1/2" PVC piping on there so when I put the panel in the gap where the spacers are, I'll be able to zip tie them without too much of a gap from the front edge of the bumper to the surface of the gap panel. I've already scraped the bottom edge of the extended air dam a few times while I'm running around Wichita but it won't make that much of a difference.

I did notice today that I need to reinforce the middle section a little bit more to keep it from deflecting under the lowered air dam.

No guts...no glory. ;)

With the way I fastened the coroplast on, I can space it out as low or as high as I need to. It won't be pretty but it will do fer now as I test it on my long runs out West to California. I'll be zipping through Dallas, El Paso, Tucson, and Phoenix. Then it will be a run out to LA and then up north to Sacramento. And then the return trip will be shortly there after. I've made runs to LA in the truck before but this will be the first time with the mods and going up north.

I might trim back the bottom edge so there's a 4" gap...maybe. I'll probably make a decision on that after most of it grinds away in the cities. :D

I thought about doing something like that for my Dodge Ram.Maybe doing it like you did,but just bridging the gap between the original air dam and bumper using black filler.The truck is a 2 wheel drive,and I can roll under it at any point on my creeper without jacking it up!We'll be waiting to hear your results.

I would consider changing the angle of it, making it look like a Delta Locomotive,

It can't be that aero friendly being so flat? maybe if you round it or cup the bottom more?

Its a great idea all the same and hope you get good results.

That would help but might get him banished from every truck club there is.
Another idea would be to cut two 6 inch holes in the front just to the left and right of the front plate. Then mount two PCV pipes angled from the holes to behind the cab; relieving some of the pressure from the center of the air dam.
I still think it will have a gain in mileage as is.