Camper top killed my gas mileage

SUP, two surfboards, and a big ARB awning. Got about 20-21 for the entire 2500-mile trip. Entire bed was loaded with camping gear as well.

 

I really think your display is at fault. Try pen and paper calculating the next two tanks of gas and see what you get.

 

Used a topper similar to yours for 6 months on 6 months off for about 5 years. No change in gas mileage.

 

Baja?

 

Si senor.

 

I recognized the fine Corinthian pavement and the empty, alluring high speed straightaways lined with large scrub right up to the shoulder from behind which a large cow may suddenly appear and challenge your reaction time and decision-making prowess.

 

There is no way that the shell alone dropped mileage from 21-22 to 14.5

I would suspect there is some unknown variable here.

OP needs to reset and run another tank to recalculate. The aerodynamics and the weight is not the issue here

 

Have had that happen a few times. Sometimes goats, sometimes horses.

Nothing gets the heart rate going like narrow roads, a semi-truck inches away going the other direction, and a 5-foot drop-off on your passenger side.

 

That bubble of air in teh bed does allow the air to flow over top before detaching and becoming turbulant past the tailgate. Most all camper shells are near vertocal or in the OP's case, slope forward somewhat but do nothing for aero except looking good.

If your interested in seeing the difference between: empty bed, roof height cap and a sloped cap check this thread out. I had run sims and the numbers are a good for a relative comparison.
MPG hit? More or less Aero designs, how do they compare? (Science and data inside) | Tacoma World

 

Wow, that’s an awesome thread you created. Thanks for sharing!

 

Can confirm.

Had a LEER 100XR and was getting 15.5 — 16 MPG.

Recently took it off and now I'm getting in excess of 18 MPG.

 

No Shit?

 

I haven’t seen any real mpg impact at all. My Snugtop Rebel shell has been on for +18 months and I still see 18.5-21 mpg, hand calculated, almost always.

 

that’s nothing. If you went from 18 to 5 MPG, then it’s bad.

The shell doesn’t hurt MPG much.

 

Mine dropped down to 13-14 MPG after a nearly empty tank and 17 gallons added. Before, I was on either side of 21. But I had the stealership take the tires/ rims ( wild peak AT3) from my trade in onto my new to me ‘21 OR ( I’ve yet to update my info on that) and my average is gradually increasing after the large amount of fuel added. I suspect the variables are the bigger tires and lack of highway travel have something to do with that .

What’s this about speedometer calibration and how often will I need to change my plugs? She’s at 28k now. My ‘08 plugs got changed every 30-35 k.


Thanks in advance

 

i was curious about this. i get a average of 16mpg for my taco. always had my camper on.

took it off for this tank of fuel.....got a average of 15.2.......so its bull crap. its just a person to person thing.

 

I’d be very surprised if results were uniform across all 4 cab/bed combinations and speeds let alone the the various additions people make. YMMV is more of a certainty than a possibility.

 

I'm around 17 in the city and 21 hwy with my leer.

 

A sample of a single tank of gas is hardly convincing one way or the other, much less to definitively declare "bull crap".

For example, the anecdotal averages I quoted above from my own experience are drawn from two years with the camper shell and then multiple tanks of gas following removal with similar traffic, weather, route, acceleration/speed, cargo load, tire pressure, time of day, and other driving conditions.

Person to person (and inherently irregular driving patterns) is certainly a variable to consider, but a shell also adds 200+ lbs with worse aerodynamics... surely it would stand to reason that's not going to benefit gas mileage.

A more scientific comparison with efforts to control all those variables would be interesting.

 

Stands to reason is just assuming a result based on a limited set of assumptions.