Drop in MPG

[koreshot]

I slapped a basic Thule ski rack on the roof of my Toyota Matrix and I notice a big drop in mileage. I used to get about 30mpg and that has now dropped to 26mpg at best. That is about a 15% drop in fuel economy.

Is this normal? I do have the Thule wind deflector on as well, but I am thinking it might actually help the drag coef if I remove it, allowing some of the air to pass under the bars instead of pushing all the air up against the ski rack.

 

[roark]

For a reasonably aerodynamic econobox that sounds about right. No personal experience here though.

 

[Warp Daddy]

yep thats on target --when i used to use roof boxes ( now no longer need them it used to cost me 3mpg on my Jetta's ) Driving a 07 Saab Sport combi stuff goes INSIDE car now

 

[bvibert]

I'm no expert, but I've read the MPG hits can vary widely from car model to model. That doesn't sound outside of the realm of possibility. Removing the deflector may indeed help.

 

[koreshot]

yep thats on target --when i used to use roof boxes ( now no longer need them it used to cost me 3mpg on my Jetta's ) Driving a 07 Saab Sport combi stuff goes INSIDE car now

I used to be able to just throw the skis in the back of the car, but the addition of a baby forced me to go buy a rack. The loss of mileage is pretty annoying from the cost, pollution and inconvenience perspective. The gas tank is pretty small, so now the light comes on every 275 miles...annoying.

 

[Warp Daddy]

I feel your pain we had to use boxes when our now Adult kids were home with us !!

 

[Marc]

Maybe you oughta think about losing a few pounds, fatty.

 

[koreshot]

Maybe you oughta think about losing a few pounds, fatty.

You kidding? All this insulation comes in handy in the winter.

 

[o3jeff]

When I had a ski rack on a Durango the mpg dropped at least 3 mpg and no matter where I positioned it on the roof, it always made a howling noise.

I have since gotten rid of it and now just fold half the back seat down int the Acura and toss them inside the car.

 

[tree_skier]

My thule spirit 1600 cost my torrent a little less then 1 mpg.

 

[koreshot]

My thule spirit 1600 cost my torrent a little less then 1 mpg.

So on the Torrent that is still a 15% reduction right? :razz:

 

[bvibert]

I was just looking at my MPG logs and surprisingly my ski box doesn't seem to be costing me too much MPG wise on my 01 VW Passat wagon, about .3 MPG on average..

 

[koreshot]

Im starting to think that the deflector might be making things worse. My wife just called me this morning complaining that she had to gas up at 265 miles on the tank, instead of 330.

 

[bvibert]

I would try taking the deflector off for sure, can't hurt anything. For the record, I don't not have a deflector on my car, just the Yakima bars and Barrecrafter box.

 

[cbcbd]

My box and other assorted racks have taken away close to 2MPG. I just have to keep my car at 70mph or below all the time or else I dip below 26MPG and I don't want that.

 

[koreshot]

My box and other assorted racks have taken away close to 2MPG. I just have to keep my car at 70mph or below all the time or else I dip below 26MPG and I don't want that.

Yeah, I have noticed that with the rack on, driving fast is particularly bad for MPG. I normally don't drive faster than 70, 75 max. I might have to drop that down to 65-70.

 

[tree_skier]

So on the Torrent that is still a 15% reduction right? :razz:

No less then 5% 22.0 down to 21.1 or 21.2 depending on the day

 

[Rook]

Are most of your miles highway miles? With the added resistance of the rack and fairing, it will cost you more mpg's with increased speeds. To counter this, I'd suggest you check and adjust your tire pressure while they are cold and make sure the car is tuned up, meaning air filter, oil and spark plugs are changed according to Toyota's recommendations. Colder weather also causes a decrease in mpg's.its partly due to winter gas and colder air temps. Good luck.

BTW I'd kill for that mileage in my V8 4Runner!

 

[ccskier]

BTW I'd kill for that mileage in my V8 4Runner!

Same here, w/ box on car, I get about 14-15, 16-18 w/ out. Will be more frugal with how long I leave it on the car this season. I do like the comfortability and security w/ a larger car on the highway etc.. w/ the family. I will take the added expense of about $30/weeked for that.

 

[tekweezle]

are you maintaining the tire pressure? that seems to be my biggest factor in gas mileage as the you lose pressure as temps go down.

also, for some reason I seem to always get better gas mileage when filling up with citgo gas as opposed to mobil. i don;t know why.....those sneaky venezuelans!