Is it true that tonneau covers save fuel?

[RobOnTesla3]

Hey everyone,

A quick question here. Has anyone noticed, that installation of a tonneau cover saved you folks some fuel? I have recently bought a cover for my RAM2500, yet didn't have a chance to install it yet. As soon as I install it, I'll post a quick mote and say, how it works on my truck. Yet, I'm curious if anyone had a chance to measure gas mileage with and without a tonneau cover so far?

[Draigflag]

I think this myth was busted on mythbusters years ago. They tried various theories, such as fitted covers and even driving with the tailgate dropped down. In the end, they found a cover made little to no difference, as you get a vortex effect with air pressure circulating in the truck bed, forcing air to go straight over anyway.

I've noticed similar when I drive with roof down, the air flows straight over the top, I see no fuel efficiency penalty for having the top dropped.

[trollbait]

A transportation agency in Canada did wind tunnel testing of varies pick up configurations. With and without the cover, and with the tailgate down.

The cover improved air drag on all trucks.

Putting the tailgate down increases drag because you lose the 'bubble' of air in the bed. Except in the case of the regular cab, long bed truck. Which is probably something only available to fleet customers these days, if at all.

[RobOnTesla3]

Wow, thanks for replying, folks.
Then I guess my own test will not show anything haha
Well, at least I will have a chance to save something that's in the truck bed from thieves

[ezshift5]

Originally Posted by Draigflag

I think this myth was busted on mythbusters years ago. They tried various theories, such as fitted covers and even driving with the tailgate dropped down. In the end, they found a cover made little to no difference, as you get a vortex effect with air pressure circulating in the truck bed, forcing air to go straight over anyway.

I've noticed similar when I drive with roof down, the air flows straight over the top, I see no fuel efficiency penalty for having the top dropped.

I can recall - as a passenger in an AH 100 with no top - driving thru a snowstorm. And sure enuff - the snow "flows strait over the windscreen

As the passenger, i did not feel a single snowflake.

Thank goodness the drive was short.



ez

[JockoT]

This is now an orphan thread.

[ezshift5]

SEMA sponsored a wind tunnel test of several pickups (IRRC)

The fuel savings noted in this test was about 1.8 per cent (IIRC)

ez