I wonder the same thing...seems like they would have no value.

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by TXSUT:
So why do the SUTs with tonneau covers have these rubber pieces? </div></BLOCKQUOTE>

Good question. I have a half-baked theory.

In the bottom of the bed are four drain holes that let water out and dirt in. With the cover, that dirt has basically nowhere to go and maybe, just maybe, there's a slight increase in pressure inside the bed while moving, which forces dust back out the drain holes and through the midgate sides if that area isn't covered.

I did notice during our last off-road adventure (while missing the right side rubber flap) the cab had a lot more dust in it. Previous runs (when the rubber piece was in place) there was only a small amount of dust.

All that hallucinating and it's not even 10 a.m.

That could be...I would think that the seal on the mid-gate would be enough...maybe not!

Last night when I opened the back of my truck, there it was, one of those flaps lying on the bottom of the bed. Gonna have to get the black silcone out again. lol

just take it out. you know you wanna!

Rodster was kidding about the dust.

I found out that the SUTs that have those flaps also have the re-mapped fuel injection giving you 50 more horsepower than the other SUTs, so I'm going to remount the flap so when people see it, they know mine is the better one.

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by VTSTOMPER:
Rodster was kidding about the dust.

</div></BLOCKQUOTE>

I was? You sound like my wife telling me what I think and all.

TXSUT -- I got the same memo today from GM tech center but really, I don't think it's the flaps. It's the enhanced aerodynamic properties of the truck as a result of the cover, which includes the flaps.

Ah, now that makes more sense.

Allegedly, they are a supplemental add on for the tonneau cover to keep moisture out if you hose out the back. The plastic pieces are stick on and a special adhesive promoter must be applied when they are installed or they will all fall down!! I think Hummer released the extra stickum after they had complaints of falling flubber errrr, I mean rubber.

exhaust fumes

you guys were totally holding out on the HP info. CRAP.

I imagine when I get my cover...wait, I mean, when I buy a cover, and it comes in. I will NOT put those stickon things on my truck. - - - unless I can get them in CHROME!