# Drop in MPG



## koreshot (Dec 11, 2007)

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 (Dec 11, 2007)

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


----------



## Warp Daddy (Dec 11, 2007)

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 (Dec 11, 2007)

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 (Dec 11, 2007)

Warp Daddy said:


> 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 (Dec 11, 2007)

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


----------



## Marc (Dec 11, 2007)

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


----------



## koreshot (Dec 11, 2007)

Marc said:


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



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


----------



## o3jeff (Dec 11, 2007)

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 (Dec 12, 2007)

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


----------



## koreshot (Dec 12, 2007)

tree_skier said:


> 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 (Dec 12, 2007)

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 (Dec 12, 2007)

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 (Dec 12, 2007)

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 (Dec 12, 2007)

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 (Dec 12, 2007)

cbcbd said:


> 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 (Dec 12, 2007)

koreshot said:


> 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 (Dec 15, 2007)

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 (Dec 16, 2007)

Rook said:


> 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 (Dec 20, 2007)

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!


----------



## X-Linked (Dec 20, 2007)

Warp Daddy said:


> 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 love my saab for that reason.  rear armrest folded down.  Could fit 4 pair of skis and still have plenty of room for 4 people to sit normally.  With heated seats.


----------



## Warp Daddy (Dec 20, 2007)

Keerectamundo  !!!  I'm on my 4th SAAB   my new combi is very cool but i've got an original equipment 1992 Turbo Scarabe green  hatchback   5 speed w/ 92,500  miles that is Cherry -- one of thelast "turtle-back" saabs


----------



## drjeff (Dec 20, 2007)

When I put my Thule Evolution 2100 on top of my Trailblazer I hold my own MPG wise.  I have it up on the Thule bars and do my darndest to align the front of the box with the top edge of my windshield.  Either way, box on or box off I'm getting a grand 'ol 17 MPG


----------



## koreshot (Dec 20, 2007)

I think some of my mileage drop is due to crap winter gas.  I also started keeping the speeds closer to 65mph instead of 70mph and noticed a decent bump in the mileage.  The shape of the Matrix roof and doors forces the rack to sit pretty far forward, which probably isn't good for mpg.


----------



## tekweezle (Dec 20, 2007)

i agree, crap gas with ethanol added will give worse gas mileage.

some things i try to do is to keep the RPM;s low and steady.   I try to cruise and coast alot.


----------



## bvibert (Dec 20, 2007)

koreshot said:


> The shape of the Matrix roof and doors forces the rack to sit pretty far forward, which probably isn't good for mpg.



I was bummed that I have to have my box over hanging the front of the car a bit in order to be able to open the rear hatch... Doesn't seem to be a real big deal on my car though..


----------



## tekweezle (Dec 20, 2007)

SUV and other tall vehicles in general have a terrible shape for wind efficiency.  I wonder if any of the new car based SUV's are significantly better.  some of them are rounded nicely like high performance sports cars.  they probably get better gas mileage than their ladder frame/truck based SUV's partially because of lower weight and ride height.

I think you can get some sort of trail hitch mounted box or basket attachment.  probably works best with RWD vehicles though since you want more weight on the rear wheels.  would suck for rear collisions and parallel parking though!


----------



## andyzee (Dec 20, 2007)

Ok, I have a solution for you. Most cars are designed to get a range of about 300 miles out of a tank of gas. You add a rack and loose 15%, this brings your range down to about 255. What I did is purchased a Toyota Corolla, this car gets approx. 30 mpg and has a 13+ gallon tank. This results in a range of about 400 miles. Now you throw on a rack and bring the range down 15%, bringing your range down to 340 miles. You're still 40 miles above your present car! 

You need to get a Corolla, if you're bitching is the price per gallon, you should not be skiing since skiing is an expensive sport. Unless ofcourse you ski with Marc and Austin which brings up a whole nother topic. :-D


----------



## Warp Daddy (Dec 20, 2007)

My 07 Saab Sport Combi sentronic tranny  gets 32 MPG with a cruising range in excess 0f 500 miles a tank  and ALL gear goes inside 

 My 03  Saab 9.3 --5 speed got 39 mpg / . 90 % of my driving IS NOT CITY driving


----------



## thinnmann (Dec 24, 2007)

One thing a roof rack that shows your skis does is it tells the world how much fun you are going to be having!  



Checkout http://www.fueleconomy.gov/feg/driveHabits.shtml


----------



## ski_resort_observer (Dec 24, 2007)

Starting to see more and more cars with two big Thule pods...that must really be a drag....:lol:


----------



## ERJ-145CA (Dec 25, 2007)

andyzee said:


> Ok, I have a solution for you. Most cars are designed to get a range of about 300 miles out of a tank of gas. You add a rack and loose 15%, this brings your range down to about 255. What I did is purchased a Toyota Corolla, this car gets approx. 30 mpg and has a 13+ gallon tank. This results in a range of about 400 miles. Now you throw on a rack and bring the range down 15%, bringing your range down to 340 miles. You're still 40 miles above your present car!
> 
> You need to get a Corolla, if you're bitching is the price per gallon, you should not be skiing since skiing is an expensive sport. Unless ofcourse you ski with Marc and Austin which brings up a whole nother topic. :-D



Yeah, Corolla is the way to go, I'll use about a half a tank on the 220 mile round trip to Belleayre.  That's driving 70-75 MPH, no roof rack, my skis are in the car.  At todays gas prices it's about $15.00 to $20.00 in gas.


----------



## SKIQUATTRO (Dec 27, 2007)

Just traded in the Nissan Arnada (12/17 mpg) was costing apprx $85/week in gas....getting the a new volvo wagon, however with 2 kids and all the gear a cargo box is necessary...good thing is it has quick release, so i can take it off and store it when not in use.....


----------



## tekweezle (Dec 28, 2007)

uphillklimber said:


> I've used the boxes on several vehicles and here's a few of my observations.
> 
> Gas mileage loss is less in Summer than winter, probably because I don't warm the vehicle up, and don't have to push thru snow. Those two factors always an issue, with or without the box. Also, the vehicle tends to get loaded a little heavier for the weekender than it would for the daily grind to and from work.
> 
> ...



i agree.  any extra weight on a lighter/smaller engine car can certainly affect gas mileage.

if gas prices continue, we are going to be heading toward having special purpose vehicles-a 4 cyl daily driver and the SUV/Minivan hauler.  I think the best you can do is to car pool to defray those runaway fuel costs.  i hope there are more choices for bus trips going forward as well.


----------



## hammer (Dec 28, 2007)

SKIQUATTRO said:


> Just traded in the Nissan Arnada (12/17 mpg) was costing apprx $85/week in gas....getting the a new volvo wagon, however with 2 kids and all the gear a cargo box is necessary...good thing is it has quick release, so i can take it off and store it when not in use.....


Is there any way to get just quick release clamps? I have a Thule box I purchased a few years ago, but to save $$ I went with the basic box which just had the basic clamps. It's a pain to put the box on the roof rack, so I usually leave the box up all season and just take the MPG hit.


----------



## bvibert (Dec 30, 2007)

hammer said:


> Is there any way to get just quick release clamps? I have a Thule box I purchased a few years ago, but to save $$ I went with the basic box which just had the basic clamps. It's a pain to put the box on the roof rack, so I usually leave the box up all season and just take the MPG hit.



I got some quick release clamps from a Thule rep to retro-fit onto an old Barrecrafter box that was given to me...


----------

