Monthly Archives: June 2013

Properly Inflated Tires Can Save You Money

If you’ve ever heard that having your tires properly inflated can improve your gas mileage and save you serious cash, you’ve probably been at least slightly dubious of these claims. How much could an under-inflated tire really cost you? The answer may be more than you think…

According to the US Department of Energy, “Under-inflated tires can lower gas mileage by 0.3 percent for every 1 PSI drop in pressure of all four tires.”

So how much money does this work out to be?

I’ve plotted the cost savings below for 3 different PSI intervals. All that you need to do is find your car’s MPG on the horizontal axis and match it up with your annual mileage on the vertical axis.

 

If your tires are underinflated by 3 PSI:

 
If your tires are underinflated by 6 PSI:

 

If your tires are underinflated by 9 PSI:

Note that these plots assume a fuel price of $3.50/gallon.

 

You can see that even at a modest 6psi, the under-inflation could easily cost you $50 a year. At the extreme, you could be wasting be well over $100 a year.

Note that this doesn’t take into account the reduced life seen by underinflated tires. Manufacturers typically claim that just 5 PSI below the recommended pressure can reduce a tire’s life by up to 25%.

Of course, with the money you’ll save using AutoGlance, you mite not even have to worry about any of this…

Money saving aside, there’s one reason to check your tire pressure that trumps all: properly inflated tires are inherently safer. Underinflated tires lead to longer stopping distances in emergency situations. Additionally, underinflated tires are frequently cited as the cause for a majority of SUV rollover accidents.

So, what are you waiting for? Go check your tire pressure!

Reddit comments on this article here.

AutoGlance Hides more than 90% of the Cars it Finds

The purpose of AutoGlance’s ‘hiding’ feature is very straightforward: we won’t show you a car if there is another listing that is better than it.

Of course, “better” is a subjective term. Which is why we’ve defined it very rigidly:

 

It’s important to note that a listing is only hidden if it meets all three of these criteria.

 

Let’s see how this plays out in different situations:

This example is as straightforward as it gets. Car A has 20,000 fewer miles, is 3 years newer, and is $5,000 cheaper. It is definitely the better car. Car B would be hidden behind Car A.

 

This example compares two much more similar cars. However, we see that once again, Car A has both lower mileage and a cheaper price. Once again, it is deemed to be a better car.

 

Now the comparisons start to get a little tricky. While Car B is $1,000 cheaper, it does have 5,000 more miles. One person might argue that the additional $1,000 is worth the reduced mileage, whereas another person might argue the reverse. This is why AutoGlance would show both of these cars; there is no clear winner.

 

Now, lets take it to the extreme:

In this case, Car B has 50,000 more miles than Car A, yet is just $100 cheaper. You’d have to be insane to argue that it’s not worth paying $100 more to get a car with half the mileage. However, this would bring subjectivity into the equation, which is exactly what we’re trying to avoid. There may be some lunatic who thinks that the car’s mileage is completely irreverent, and thus would buy Car B over Car A. This is why AutoGlance would once again show you both cars in this scenario, because no car is clearly,unquestionably, better than the other.

 

Of course, the method is not perfect. For example, lets look at this scenario:

While Car A is $100 cheaper, it is in poor exterior condition. Knowing this information, most people would probably purchase Car B (even though it would have been deemed a worse car by AutoGlance). Unfortunately, car condition is rarely something mentioned in any online listing, and there’s no way of knowing this without going to the dealership and checking out the car in person.
The upside is that Car B is more than likely the very first car hidden behind Car A, so hopefully you wouldn’t have had too much trouble finding it. While the cars we choose to display are almost always the best deal you could find given the available information, we certainly recommend checking out the first few cars that are hidden behind it.

If all this looks mighty familiar, it may be because you’ve seen something similar on the flight search engine Hipmunk. Their interface is indeed what inspired us to build this feature, and we certainly owe them some credit.

It’s worth noting that hiding cars is an extremely delicate process, and that AutoGlance has developed an extensive filtering system to make it work. For example, all you need is one listing for a damaged or accident vehicle, and the heavily discounted price would cause hundreds (or even thousands) of listings to be hidden behind it. The same would occur for a listing where the seller fumbled when typing his asking price and wrote $36,000 instead of $63,000. Figuring out how to eliminate these scenarios was by far the most difficult aspect of the system, and we’re glad that we’ve got it working as well as it does.

If you have any suggestions on how we can further improve the hiding feature, we’d love to hear them. As it stands, we think we’ve done a fine job of taking 1,000’s of search results and presenting them in way that makes it easier for you to find the best deals . It certainly beats sorting them by price, mileage, or an arbitrary deal score, and forcing you to look through them, one by one.

Well, what are you waiting for? Try searching AutoGlance for yourself.