pintado

In an attempt to improve my 2013 ES350 gas mileage, I decided that the 300h rear deck spoiler must be part of the secret. All of the 300h's have a spoiler; I haven't seen any 350's with one. So, using a $200 CostCo Purchase parts/accessories voucher and a 15%-off parts/accessories coupon from my Lexus dealer, I got the factory spoiler and mylar template from Lexus. My total out-of-pocket was about $50 including tax. It took me about 1.5 hours to install the spoiler, including time looking for tools (Where's my reamer?, What happened to the 8mm socket?, etc.). The color match is near-perfect. I'm just waiting for the mileage to start climbing...

winsalem

"...I decided that the 300h rear deck spoiler must be part of the secret."

I think this may be a joke. I sure hope so.

Mike728

I sure hope so, too.

GES

I do believe the spoiler does improve fuel economy; otherwise why make it standard on the hybrid and not on the ES350. It cannot be just for looks. It has to do with the airflow over the trunk. The improvement may be very little though. This is just my opinion.

Arty101

I think he must be joking too, although $50 for the spoiler is unbelievable.

LexRuger

Would make a good Mythbusters episode.

a310pilot

You do realize you have a V6 3.5 L engine VS hybrid with V4 2.5 L engine,

GES

This is a quote from a website called cardata.com

The main design goal of a spoiler in passenger vehicles is to reduce drag and increase fuel efficiency. While many often imitate wings and airfoils, these serve mostly decorative purposes. Passenger vehicles can be equipped with front and rear spoilers. Front spoilers, found beneath the bumper, are mainly used to direct air flow away from the tires to the underbody where the drag coefficient is less. Front spoilers are also called air dams because in addition to directing air flow, they also reduce the amount of air flowing underneath the vehicle which reduces aerodynamic lift. Rear spoilers, which modify the transition in shape between the roof and the rear and the trunk and the rear, act to minimize the turbulence at the rear of the vehicle

To put it another way, spoilers function by disrupting or diffusing the airflow passing over and around a moving vehicle as it passes over the vehicle. This diffusion is accomplished by increasing amounts of turbulence flowing over the shape, "spoiling" the laminar flow and providing a cushion for the laminar boundary layer. Often spoilers are added styling purposes only, however the fuel economy has to be a new consideration.

gmanusmc

Do you all REALLY THINK there's a possibility that he's not joking? Really?

Mike728

If this was not just a goal, but an actual fact, all cars would come with it.

wasjr

I will admit that I assume that the spoiler helps fuel economy, otherwise why is it standard on the 300h.and not on the 350? My thought is that Toyota did all they could to achieve the 40 mpg rating on the hybrid, and the spoiler helps do that.

GES

I agree. May be the difference in fuel economy is small that doesn't justify adding it to every car. But in a hybrid fuel economy is very important, especially if you are competing with other hybrids. Then every bit helps. Most SUVs though do have a rear spoiler.

winsalem

Yes, I agree with GES. As for the estimated improvement: According to my brother the pilot, the mileage improvement gained by a spoiler such as this would be seen at speeds over ~ 80 to 100 mph.

In the past, Lexus has added standard spoilers to some models in an effort to increase the sportiness, not MPG. And to help justify the add'l price of the car. Both of my GS's came with a standard spoiler.

Just my $.02...your mileage may vary (literally)

Mike728

Those are there to keep dust off the rear glass.

Seriously, people... At legal speeds, these cosmetic spoilers are just that.

pintado

Since installing the rear spoiler on my ES350, I've not yet noted a significant increase in gas mileage, but I have noticed that the air pressure in the rear tires has increased by 1psi. I suspect that the pressure increase is caused by airflow passing over the spoiler and pressing down on the trunk, squeezing the tires.