Huh, a completely different bumper on a truck with a lower towing capacity, you don't suppose they, nah, well maybe designed the bumper with different airflow properties than the stock truck do ya? You weren't seriously using the ZR2 as a basis for comparison were you?Not sure where you got a figure of $136 for GM to print it in the owners manual?
Also, I guess I have to stand corrected. l I couldn't find anything about installing an airdam on the ZR2. Oh wait.........
Just think, you could have had a 23 mpg average if you left it on or 24 mpg if you chose a better tire... I do think it is not very good looking but it is far from useless.Here, I’ll put this to rest. I have 100K on my 16 Colorado and have had the air dam off since Day 1. I get 22 highway with a 1” inch lift and KO2s.
The air dam is hideous and useless. Remove it.
On the Silverado at straight highway speeds of 75 mph over 25 miles back to back that slightly smaller airdam (compared to the canyon/colorado) is good for just over 1mpg versus removing it. It does help with mpg first and foremost; if there wasn't a scenario in testing the engineers came across where it caused excessive heating of the engine they wouldn't have put it in the owners manual. So obviously some sort of testing they did they found the engine heating up with it off versus on, most likely in a scenario none of use will come across. It is comical people even debate this or think they know more than the people who designed and tested the truck in situations far worse than anyone here has put it through... Those who say it has no impact just aren't noticing the 0.2 mpg difference over all their driving in city that offsets it or aren't reading and tracking their engine temps to the degree to notice that couple extra degrees they may be running at with it off versus with it on.
DETROIT – The all-new 2014 Sierra full-size pickup truck spent more development time in a wind tunnel than any GMC pickup before it, resulting in design changes that benefit both fuel efficiency and interior quietness.