Wednesday, October 21, 2015

Scotch Nature: Tire Gauge

Disclaimer: As with much of the Scotch Nature series the following advice will be head-poundingly obvious to many people. Congratulations you probably aren't part of the 48% of America that would have to go into (more) debt to cover a $400 emergency.  Someone decides they that they're sick and tired of being sick and tired and start looking for how Great-Gramma managed to raise 5 kids on whatever a widow could scrape together in the 30's and need a gateway drug to common sense.
You can improve your gas mileage by up to 3.3% by keeping your tires inflated to the proper pressure. Under-inflated tires can lower gas mileage by 0.3% for every 1 psi drop in pressure of all four tires. Properly inflated tires are safer and last longer.1
The proper tire pressure for your vehicle is usually found on a sticker in the driver's side door jamb or the glove box and in your owner's manual. Do not use the maximum pressure printed on the tire's sidewall.

 So let's say you drive a mostly reliable car that gets about 25mpg now lets say that instead of 30psi in each of your tires you are running closer to 25psi. Now let's assume that you dive about 150 miles per week, and gas where you live is $2.50 per gallon. 25mpg x (0.3% x 5psi) low= .375 mpg

Cost of one week driving @ 25mpg = $15

Cost of one week driving @ 24.625 = $15.23

Now I know $0.23 doesn't sound like much but lets take 52 weeks a year $11.96.

Or nearly 20lb of pinto beans at Sam's Club.

Just do me a favor dig out on of the tire gauges your dad is always giving you as a stocking stuffer find a store with a free air hose and properly inflate your tires once a week for a month and see if you are putting in fewer gallons(spending less or more depends on whether Putin accidentally bombs an Sunni pipeline or other big things out of your control).

Now who here has a messy car*raises hand* yes friends I too am a messy car sinner. So I challenge all of my fellow messy car sinners to this very weekend grab a trash bag and their bathroom scale.

From what I’ve read, the fuel of thumb is: For every extra 100 pounds you carry in your vehicle, you reduce gas mileage and fuel economy by roughly 2%.
 Now I'm not going to look but who here has a whole bunch of range targets, sand bags, and assorted other unlikely "tools" in their truck that come up to 100 lbs. Don't get me wrong having tools handy is good and can save you trips, but if you're carting this and 30lbs of trash around in your floorboards you are literally paying for it.

Let's just use 100lbs for a round number could be less but I can name several friends who have way more excess in their truck campers and trunks, not to mention floorboards.

Let's take a 20mpg truck x 2% unneeded load =  .4 mpg

At $2.50 gas(these numbers go up if gas does) we have $18.75 to run it 150 miles per week just for gas.

Now with 100lbs of stuff you probably don't need we have $19.13 to run it that same 150 miles per week.

So over a year that $0.38 per week comes to 19.76. Now I hate hauling the sand bags and targets in and out of the shed as much as then next man but I wouldn't mind an extra box of ammo or two to practice each year.

So many people are considering buying a car they can't afford and spending hundreds of dollars of interest each month(don't get me started on depreciation) to safe a few bucks on gas that they never stop to ask if they are getting the best they can out of what they already have.


  1. Properly inflating your tires saves you .23 cents a week.

    Driving well out of your way to find an air pump that works.... an extra $1.33 in gas a week :)

    I am only half serious although I think you know that. Your point about the car payments is some good advice. One I live by.

    1. Most of the Casey's around here have working free pumps and aren't out of the way. Besides just how many compressors do you have on the Small Hold? ;_