Its not always about MPG

[Tahoe_Hybrid]

here is some photos you can see the Aero issues that are quite visible


the mirror is not small it's huge i have a 10 inch hand span you can see how big it is



Objects are bigger then they appear in the photos due to the extreme wide angle of the lens

[ennored]

You need to compare your Tahoe to a regular one. You'll find a lot of aero tweaks have been done. So the small stuff has already been done. I'll google, see if I can find a list of differences.

Edit:
Fist find, the GM list:

Aerodynamically enhanced exterior:
Aluminum hood and liftgate
Lowered front air dam
Aerodynamic assist steps
New rear fascia, rear spoiler and D-pillar appliqués for aero improvements
Lightweight aerodynamic aluminum wheels
Low rolling-resistance tires

I know that's not a complete list, as I know the panels above the taillights are unique, and not listed.

Should be able to find the Cd improvement too...

edit:
Looks like .379 to .360 And aero mirrors are mentioned.

https://gmauthority.com/blog/2010/06...g-coefficient/

[Tahoe_Hybrid]

The original version above.

the original is 0.363 and this is 0.34

yeah not much lower

[ennored]

So you do know about the tweaks. As I said, it's just going to make it tougher to find little things that help.

And you realize something like 80 or 90% of the emissions are due to cold start and warm up on the EPA cycles, right? The next big chunk is transient and intrusive diagnostics. Steady state emissions, driving down the road, are effectively zero. The cats are converting everything to water and CO2.

You will cut CO2 though, if you are considering that.

Are those numbers for the '13 model? Did it change? Stuff I found was old, but only mentioned the first couple years.

[Tahoe_Hybrid]

Originally Posted by ennored

So you do know about the tweaks. As I said, it's just going to make it tougher to find little things that help.

And you realize something like 80 or 90% of the emissions are due to cold start and warm up on the EPA cycles, right? The next big chunk is transient and intrusive diagnostics. Steady state emissions, driving down the road, are effectively zero. The cats are converting everything to water and CO2.

You will cut CO2 though, if you are considering that.

Are those numbers for the '13 model? Did it change? Stuff I found was old, but only mentioned the first couple years.

the next update was 2015 which the front end changed 0.34 and smaller mirrors (these mirrors can be modified to fit on mine) but it's pricey at about 350$ for just that the 2019 might be slightly lower as they added air ducts

the biggest drag in the front is the mirrors, because of the size of them.



you can hear the wind dragging on them at about 75 or so


the only reason i'm able to get the good mpg is because i use 91oct as it's able to keep it in V4 mode much longer then 87oct ( it hyper switches from v8v4v8 i'm pretty sure that is bad for the engine i.e wear and tear wise to the AFM system )

[Tahoe_Hybrid]

Originally Posted by ennored

So you do know about the tweaks. As I said, it's just going to make it tougher to find little things that help.

And you realize something like 80 or 90% of the emissions are due to cold start and warm up on the EPA cycles, right? The next big chunk is transient and intrusive diagnostics. Steady state emissions, driving down the road, are effectively zero. The cats are converting everything to water and CO2.

You will cut CO2 though, if you are considering that.

Are those numbers for the '13 model? Did it change? Stuff I found was old, but only mentioned the first couple years.

I was thinking of a full skirt wrap around and drop the front to about 1" of clearance. sides 2 inch of clearance ridged but needs to be flexible if anything in the road .. i'm just wondering what everyone else uses

[Ecky]

Lawn edging or conveyor belt material work well. I've used the former on a vehicle - it got torn up during a Vermont winter, but so does literally everything else.

[Tahoe_Hybrid]

Originally Posted by Ecky

Lawn edging or conveyor belt material work well. I've used the former on a vehicle - it got torn up during a Vermont winter, but so does literally everything else.

I did some clearance checks

and the front has

8 inches

sides have 10 inches

the rear at the muffler is 13 inches



would a bigger airdam help?

[Ecky]

I've read the air dam should hang down as far as the lowest point on the underside of the vehicle, any lower and it's increasing frontal area, which adds drag. I can't cite my source, but if true, going all the way to the ground would be counterproductive.

[Tahoe_Hybrid]

Originally Posted by Ecky

I've read the air dam should hang down as far as the lowest point on the underside of the vehicle, any lower and it's increasing frontal area, which adds drag. I can't cite my source, but if true, going all the way to the ground would be counterproductive.

but it does look like it has some Parachutes type items under it, especially the rear bumper..



how about wheel splats? I was thinking of using 18 wheeler mud flaps(cutting them though) it's 33.30$ for a pair to do all 4 tires

the 2015+ has built in wheel splats to the front air dam..
.



but i think might be able to do a Vent duct where those plastic covers are ?