Archive for May, 2014

Buying a Used Vehicle? What to Look For: A Mechanic’s Perspective

Monday, May 19th, 2014


Depending on your situation, buying a used vehicle can be a very smart decision. New vehicles usually lose as much as 50% of their value over the first couple years, giving savvy shoppers a chance to purchase a “near new” vehicle while letting somebody else take that big depreciation hit. Vehicles are built much better today than in decades past, so even a 10 year old used car should be expected to provide you with many years of very reliable service – providing it has been cared for.

As an auto repair business, we get to see the good, the bad and the ugly of the used car buying process. Sometimes a customer’s new purchase turns out to be a great buy, and sometimes it goes the other way! Based on the problems we see regularly, here are some tips to consider when shopping for a used car:


  • Have the vehicle inspected before you buy it. You’d think this would go without saying, but we actually do way more “post-purchase” inspections that pre-purchase checks, and often the customers are less than impressed with the results! A good pre-purchase inspection can arm you with the information you need to make an informed buying decision, and serve as a bargaining chip if the vehicle requires any repairs.
  • Check the maintenance history. This is another obvious one, but often overlooked. The more thorough the owner’s records, the better. A bunch of invoices from one repair business can indicate that the owner has built a relationship with a local company and is dedicated to looking after their car. Look for patterns such as a future repair being recommended on one invoice, and then being completed on a later one – did the owner follow through with the shop’s recommendations? A stack of invoices from 10 different shops can indicate that the owner might be a “price shopper” and less concerned with quality; and certain services may have been neglected or overlooked.
  • Have a mechanic look through the maintenance records. Automotive service invoices are sometimes difficult to decipher, and can contain mechanical jargon that’s hard to understand. Someone in our field can help you understand exactly what services were performed on these invoices, and can pick up on certain issues you might overlook, such as if the wrong fluids were used, etc.
  • Find out who was driving the vehicle, and why they are selling it. The best used vehicles come from people who purchase a vehicle for their own personal use and drive it for several years before selling because the vehicle doesn’t fit their needs anymore. Rental and company-owned vehicles are often operated by many different drivers, none of whom are too concerned with the vehicle’s well-being! Also, be wary of backyard “car-flippers”; these are people who purchase vehicles in order to repair them and sell them later for a profit. These people are usually operating without an AMVIC license and the vehicles often exhibit substandard repairs, slapped together with used or cheap parts.
  • Take the vehicle for a thorough test drive. Don’t feel guilty about asking for a proper, longer test drive! If the seller really wants to sell you the car, they’ll agree to it. Ask to be able to start the engine cold, after it has been sitting for many hours, or preferably overnight. Many abnormal engine noises and other problems will only show up when the engine is cold. Following the cold start, drive the vehicle under different speeds and conditions for at least 20 minutes in order to fully warm it up. This will allow you to adjust to the vehicle and pick up on things you wouldn’t have noticed on a quick “around the block” road test. It will also allow you to catch any problems that only show up once the car is hot.
  • Look for little warning signs. There are sometimes warning signs that can tip you off about a vehicle that hasn’t been cared for that well. This can include broken or missing interior trim; features and options that don’t work; a bunch of bulbs burnt out; even tires that haven’t been rotated (quite worn on the front, and like new on the rear; or vice versa). Is the “change oil” light on, or is the vehicle way past the mileage on the reminder sticker? While these aren’t big issues by themselves, they can be signs that the owner hasn’t taken pride in the vehicle, or their mechanic hasn’t been doing a great job helping them keep the car in prime condition.
  • Be wary of vehicles that were in a recent collision. Even after a body shop restores a damaged vehicle to like-new condition on the outside, there is sometimes concealed damage which doesn’t show itself right away. This could be something like a punctured air conditioning compressor tucked behind that brand new bumper, which you don’t find out about until summer. Even worse, a lifetime of strange electrical problems can be caused by crushed or chafed wiring harnesses hidden behind new body panels.


In a future post, we’ll dive into other aspects of the used car buying process, like “Is a Carfax report worth it?” and “Should you buy an extended warranty?” so stay tuned!

Understanding Tire Sizes

Friday, May 9th, 2014

We get a lot of questions about tires, and tire sizing, which is no surprise because the sizing format that has become the industry standard couldn’t be more confusing. What do all those numbers on the sidewall of your tire mean? Let’s break it down:


Airdrie Tires


  • The section width is pretty straightforward. This is the width of the tire, in millimeters.
  • The aspect ratio is where things start to get confusing. This is the height of the tire sidewall (from rim to tread), but this is expressed as a percentage of the width. For example, this tire’s sidewall height is 75% of 185mm, which is a little under 140mm. Because the aspect ratio is a percentage, a 195/75R14 tire is actually wider and taller than say, a 185/75R14 tire.
  • The “R” construction method means this is a radial tire, as with almost every tire produced today.
  • The rim diameter is expressed in inches – yes, we’re mixing metric and imperial measurements here for some reason! This tells us what diameter of rim this tire will fit on.

These measurements all often all that is considered when most customers shop for tires, but there are two more very important numbers on the side of your tires that shouldn’t be overlooked:

  • The load rating tells us how much weight the tire can support at its maximum air pressure without failing. For obvious reasons, your tire’s load rating should meet or exceed what is required by your vehicle.
  • The speed rating of the tire is often misunderstood. In theory, this number tells us how fast a tire can be driven without failing, but even cheap “S” rated tires are rated for 180 kilometers per hour! The ratings continue to increase as you move towards the end of the alphabet.

So, why not just put “S” rated tires on every vehicle? You’re not going to drive that fast, right? In reality, the speed rating tells us a lot more about the construction and stiffness of the tire – how it brakes, corners and grips – even how much it heats up travelling down the road. It is absolutely essential that your tire speed rating meets the standard required by your vehicle in order for it to handle and perform the way the manufacturer intended.

Recently, Global News showed a story where they equipped two Mazda sedans with new tires; one with the recommended “V” rated tires, and one with cheaper “S” rated tires. Not only did the car with the right tires ride and handle better, it also stopped a whopping 23 feet sooner when both vehicles had to brake hard from 80 km/h. This could be the difference between life and death in some situations.


Airdrie Tire Shop


Most newer vehicles have a tire size placard, similar to the one above, which will show you what size (plus load and speed rating) of tires your vehicle requires. It will also show you the manufacturer’s recommended tire pressure. A quick note on this: Always set your tire pressures to the recommendation on this decal. The tire pressure shown on the sidewall is the theoretical “maximum pressure” of the tire, and may be way too high for your vehicle!