Fixpoint

Relatives are looking into buying a used car, so I've dug out the checklist that served me well enough the last time I did this just over ten years ago, and expanded a bit.

I gather the major trends since that time have been toward ever flimsier materials⁽ⁱ⁾ and integration of complex electronics into core vehicle functioning.⁽ⁱⁱ⁾ Nonetheless, the basics won't have changed much.

Used cars are, of course, the canonical example of what economists call "the market for lemons": there's an inherent asymmetry of information in favor of the seller, so buyers are rightly distrusting and won't pay what a car might well be worth, so the good ones are less likely to go on the market at all, leading to more distrust and so on. The only way out, such as it is, is to mitigate the asymmetry; that is, by having a clue. If you don't have strong mechanical knowledge yourself, be sure to get the vehicle checked by a mechanic you trust.⁽ⁱⁱⁱ⁾ If the seller won't let you, move on.

That said, you can still learn things and save time by doing as thorough a pre-check as you can on your own. When going to check a vehicle, be sure to bring:

• Pen and paper
• Flashlight
• Paper towels for checking oil
• Tire pressure gauge

Inquire as to the vehicle's history (single-owner is preferable). Are service records available? Has it been involved in an accident (not necessarily a dealbreaker if it was minor, but definitely affects the price)? Has it been in a flood (dealbreaker)? Is the title clean? If possible in your market, use a service like Carfax to corroborate these. If buying from a dealer and looking for a warranty, what's the current status or cost of extending?

Of course there's the question of whether it fits your needs: cost, comfort, safety, size, storage space, power, looks and so on. If you're into hybrids for some weird reason, note that like all batteries, the hybrid battery degrades over time, but is much costlier to replace than a conventional lead-acid starter battery.

Moving on now to the the parking lot self-check; first the exterior:

• Check the body lines (silhouettes, reflections) for dents, and panel paint colors for unevenness (i.e. indicating undisclosed repairs).
• Check gaps (door and hood perimeters) for even width.
• Check tires: tread wear patterns; sidewall damage; that they're a matched set and of a reputable brand; pressure; spare; changing tools (jack and lug wrench).
• Look for corrosion, particularly on the exhaust system.
• Under the hood: check belts, fluid levels, and that all caps are present. (This is a good basic safety check before even taking a test drive. I was once shown a car with no detectable oil level!)
• On the (cold!) engine, remove oil filler cap and check its underside for suspicious residues.
• Check that door handles have little free play and the doors can lock and unlock manually. Check opening and closing of doors, trunk, hood, gas door and gas cap.
• Check suspension by bouncing each corner (gently but firmly). There shouldn't be a repeated bounce.

Interior:

• Check presence of owner's manual (glove compartment) and manufacturer label (driver's door jamb).
• Check odometer.
• Check all electrical components: headlights, high beams, fog lights, turn signals, emergency flashers, taillights, brake and backing lights, power locks, power windows, HVAC, seat adjustment, mirrors, wipers and pump, sunroof, stereo.
• Check condition of seats, headrests and seatbelts.
• Check for smells and signs of moisture. If there's a foul smell: it's probably never going away. If there's a pleasant smell: what's it covering up?
• When cranking, check for smoke (suggesting oil leak) and excess noise or vibration.
• Check dashboard warning lights and gauges.

On the test drive:

• When safe, check acceleration; there should be no hesitations.
• Check for smooth shifting, reverse, and downshifting.
• For manual transmission, check for clutch slip (e.g. floor it in second or third and check that tachometer doesn't outpace speed). Check synchronizers on first and second (i.e. smooth engagement from neutral immediately after disengaging clutch; these do wear out and it's fine to do without but takes more finesse.) For automatic, check that shifting is responsive enough for your taste.
• Check main brakes and handbrake.
• Check handling on turns.
• Check performance of suspension on bumps if possible.
• Check cruise control.

Good luck, and may you find a suitable mechanical beast to serve you for years to come. Take care of it and it'll take care of you!

1. For fuel economy and the environment, of course. Surely not because the consumer can't afford steel anymore, nope, couldn't be that. [^]
2. This mirrors the constant push for convenience at the cost of technical comprehensibility and robustness seen in the computing industry proper, as well as the near extinction of the manual - once "standard"! - transmission at least in the US market. [^]
3. In Latin America I never met anyone who knows a mechanic they trust (though to be fair, I wasn't looking very hard). In the US, cars tend to be both more affordable and more essential, while the poor are - for so long as the dwindling reserves of government largesse hold out - not actually all that poor, so virtually any long-term resident in a given location will have their war stories and recommendations, so this part of the search is easier. [^]