Friday5: Tips for maximizing MPGs

fuel-gauge.jpgGas prices suck. I know it, you know it, we all know it. Nobody likes to spend more on fueling up their vehicle than necessary, right? I didn’t think so. Fortunately there are a number of easy steps that anyone can take to maximize their miles per gallon (MPGs.) This week’s Friday5 tackles some of easy ways to go farther on every drop of fuel.

(To help envision the potential savings of each of these tips I’ll do a little math using some baseline figures. In order to see how much you could save, lets pretend your car gets 20 MPG, you drive about 12,000 miles a year, and a gallon of regular unleaded gasoline costs $3.29, which happens to be the national average as I’m writing this.)

1. Get Pumped Up

Most cars driving on the road today do so on under-inflated tires. You can find out what the proper pressure for your vehicle’s tires is by checking the driver’s side door jamb for a sticker with the information or looking in your owner’s manual. Tire pressure gauges are very inexpensive and easy to use. Most gas stations have air pumps or you can buy your own that will run off your car’s power socket. Checking your tire pressure every two weeks and keeping your tires properly inflated could help you get up to 3% better gas mileage. While that may not seem like much of a difference (from 20 to 20.6 MPG), over the course of a year it adds up to over $50.

2. De-Junk Your Trunk (And Lose the Rack!)

The heavier your vehicle is the more fuel it will need to get from point A to point B. This is one of the reasons big SUVs and trucks use so much of it. One easy way to lighten your load and increase your fuel efficiency is to keep the inside of your car cleaned out. An extra 100 pounds can decrease your mileage by up to 2%. The smaller and lighter your car is the more you will benefit from this. However, not all cargo is necessarily carried inside your vehicle. Large, bulky roof racks can also greatly impact fuel mileage. This is due to both their weight and their poor aerodynamics. Removing a large accessory rack from your car or SUV can provide a 5% or greater increase in MPGs. Taken together, these result in a savings of $130 annually using our figures.

3. Slow It Down

When driving down the interstate peer pressure is a powerful thing. When everyone else is doing 75 MPH it feels foolish to not do the same. However, slowing down just a little bit on the highway can provide a huge savings in fuel economy. Under about 45 MPH the primary resistance a car encounters is rolling resistance between the tires and the road. Above 45, air resistance becomes the biggest factor. Air resistance increases exponentially with speed, so the faster you go, the more your gas mileage drops. The math on this one is difficult to estimate, as it is hard to tell what percentage of your driving is done on the highway, at what speeds, and how aerodynamic your vehicle is. According to the U.S. Department of Energy it’s safe to say that each 5 MPH you drive over 60 MPH is like paying an additional $0.20 per gallon. Let’s say that you switch from driving about 3,000 miles annually at 75 MPH to doing the same at 70 MPH. That’s at least a $30 savings. Plus it’s safer too …

4. Breathe Deeply

Ok, this one may require getting your hands a little bit dirty. But just a little bit, I promise! In order for your engine to operate as efficiently as possible it needs lots of fresh air. Your car’s air filter makes sure that air is as clean as possible when it enters your engine. After a while the filter begins to get clogged, which is not necessarily a bad thing because that means it’s doing its job! Once the air filter starts to get dirty your engine can’t get as much air as it needs, and it begins to run less efficiently. Most manufacturers recommend replacing your car’s air filter every 12,000 to 15,000 miles for peak efficiency. This may seem like a lot of air filters, but replacing a dirty air filter can increase your car’s mileage up to 10%! That’s a jump from 20 to 22 MPG and a savings of $180 in a year, which is definitely worth the cost and trouble of replacing a $15-$20 air filter.

5. Don’t Sit Idly

Excessive idling can wreak havoc on fuel mileage. Remember, when you are sitting still idling you are getting exactly zero miles per gallon. You may have heard that starting and stopping your engine repeatedly will produce excess wear. While this can be true, if you have a relatively modern car and take care of normal maintenance like oil changes and tune-ups then you have nothing to worry about. Here again the size of your car can make a big difference. The larger your vehicle’s engine the more fuel it will use while idling. Sometimes idling is unavoidable, but times like sitting in line at the drive-thru or waiting to pick up a friend are perfect opportunities to shut down your engine and get more for your gas money.

Assuming all of these tips apply to your situation, these 5 tips combined could result in a whopping 20% increase in miles per gallon. In our hypothetical scenario that’s a potential yearly savings of around $350! I know there are plenty of other ways to increase your fuel mileage and decrease the amount of money you spend on driving around, so feel free to share some of your favorite tips and tricks in the comments.

And as always, your mileage may vary …

Friday5 is a weekly column that lists five items on a theme drawn from one of the various categories covered by From Bits to Bites & Windshields to Worship.