Better MPG With Bed Cover

I just did the same 500 mile trip in the last month, with and without Diamondback HD bed cover. Without the cover got 19.1 MPG, with the cover I go 21 MPG. Surprising improvement. Weather was the same - mostly highway driving. Half the trip going 80 in AZ other half going 70 in NV.

 

Claims have stated it's a myth. Along with leaving the tailgate off or on. It is my understanding there is a vortex created inside the bed at highway speeds...

 

I was also surprised at the improvement. Around town its the same. This was the same exact trip, I even parked in the same parking garage spot . Weather was sunny and around 60 degrees for both trips (not much wind).

 

How many miles total on the truck?

 

First trip I had a little over 1,000 when I started. Second trip I had around 1,700 when I started. Used the ACC on both trips.

 

My last four trucks have had bed covers. I have noticed no increase in mileage in any of them.

 

Probably just breaking in

 

You would think 1,000 miles would be broken in.

 

sample size is not nearly enough to make any definitive conclusions

 

Didn’t change anything for me.

 

Even just a small amount of wind or a small change in its direction or velocity that wouldn’t have been noticeable by you is enough to affect your gas mileage.

 

By 10%? Doing same trip in a month will report back. Does not really matter anyway, MPG is still crap.

 

Not even close.

 

I get around 22-23 mpg at 76 mph on western Pa. highways. Doesn’t matter if bed cover is on or off.

By comparison I was getting around 20 mpg under same circumstances in my 2019 …love the little turbo.

 

Ahhh, you must be a first time Tacoma owner. Over all the years that I drove my Gen 2 Tacoma, which was built almost identical to my current Tacoma (except everything is way different), I consistently averaged 17 mpg.
j.

 

Yeah first Tacoma - use it as our third car to run errands and park at airport.

 

My average mpg permanently dropped to 0.1mpg less when I added the OEM bed cover. 6k miles without, 2k miles with

 

I have the Diamonback tonneau cover on my shortbed TRD OR. I wonder if it will change mileage at all. My first few tanks (without cover) averaged about 15 mpg.

 

How much do those diamond back covers weigh?

 

negligible at best, TFL I believe got 1mpg improvement.