Really Crappy Gas Mileage - ideas??

[Somedude]

overinflation on the tires can also cost you more, the tire wears out faster. And it can be dangerous because as tires heat up, the tire pressure builds up and the risk of blowing a tire while driving increases.

Lets say the maximum pressure of a certain tire is 45 psi, that doesn't mean you pump it up at 45 psi. It just means the tire can withstand up to that PSI number.

Right now I pump all four of my tires to 32 PSI, the manual says 29 PSI which is kinda low, so I didn't follow it.

[Mayor]

Somedude - you are correct. The max PSI for the 17" standard tire is 42 PSI - that is why I suggested 38 to 40 PSI. That will give you good gas mileage but somewhat of a stiffer ride.

Thanks,

Mayor

[MrMikeL]

u should have drop by and said hi to me in Des Moines

We arrived at 1:15 AM and were on the road to Chicago at 8 AM. Not sure you would have appreciated a visit at tiose times!!

Alignment right before the trip was checked out as OK. I have serviced my K&N filter just once, and will probably do so once every 20k miles.

Thanks for the tips everyone! I'll try some of them on my 500 mile trip next week to central Wisconsin. Anyone in the Waupaca area???

[stockae92]

overinflation on the tires can also cost you more, the tire wears out faster. And it can be dangerous because as tires heat up, the tire pressure builds up and the risk of blowing a tire while driving increases.

Lets say the maximum pressure of a certain tire is 45 psi, that doesn't mean you pump it up at 45 psi. It just means the tire can withstand up to that PSI number.

Right now I pump all four of my tires to 32 PSI, the manual says 29 PSI which is kinda low, so I didn't follow it.

ditto, not to mention that you have less traction (less rolling resistant, hence better mpg). that is in the expense of braking and cornering performance. (e.g. in case of emergency braking, more traction is a good thing)

so its all a trade off of traction, tire wear and mpg.

i personally put 34-35psi in the front and 33-34psi in the rear (always the same for left and right though)

you can always play around and experiment with the tire pressure and see what works the best. but i would go from low to high just to be in the safe side.

rolling resistant is bad for mpg. but over inflated tires are dangerous as well. your call.

[FLUXEMAG]

2-5MPG with AC could be correct if you start out at the top of the curve where you drive like Grandma, only on highway, cruise control with ultra high tire pressure on ice. Maybe 0.5MPG for people in the mid to low range of our fuel economy expectations. I saw negligable difference between winter and summer. I live in PHX so my AC is never off max in summer. I consistently get 23MPG cum regardless of season and I drive such a consistent route that I see the same people on the roads with me every day. Fun stuff eh? However I did a test two weeks ago, for an entire week, where I drove below 3k RPM and seriously pissed off other people with my conservative pedal use. I got 29MPG, with AC on full blast nonstop. Not worth the frustration or time to save a few bucks.



Were you driving up hill, or in high elevation?

[MrMikeL]

OK, I just got back from my second long trip this month, though shorter than the first one. The gas mileage is still very disappointing at about 26 on the highway. I even pumped up the tires a bit to be sure. I will try to get it into the shop during the next couple of weeks for an oil change and I'll ask them about it.

[jimhild]

You dont use the DOOR sticker to gauge your Tire preasure. Look ON the tire and as I said, if you have the standare 17" tire, the max PSI is 42. If you DONT have the standare tire, then again, look ON the tire.

So if you are running 32 PSI on tires that have a MAX of 42 - that will explain why your mileage is so horrible. The back profile of your tires probably look like a bag of coins on a flat surface - much harder to spin them and directly affects your mileage.

Thanks,

Mayor

Mayor, I beg to differ with you. The proper inflation is on the door sticker. The number on the tire is Max Pressure. The high pressure will lead to worn out centers of the tires and a very hard ride.

Use the pressure indicated on the door sticker and check/set pressure when tires are cold only.

[Turbosolara]

oh it might be depend on what kind engine oil you used. one guy i knew tried and it made a big difference in mpg. i think 5w-30 is the most consevative efficient motor oil.