A careful evaluation will help you stay away from hidden problems.
Before closing the deal, take any used car you’re considering purchasing to a mechanic for a thorough inspection.
By Jon Linkov
Finding a problem-free used car has nothing to do with luck, but rather the application of good research and the skills of that analysis. Knowing how to spot potential problems and determine how reliable a used vehicle is can save you costly headaches down the road. The following tips help you avoid problems and find a good price.
Start by researching everything you can on the Internet. Once you’ve found one or two cars you’re interested in, whether sold by a dealership or privately, start evaluating their condition and history by contacting the seller via email, phone, or text message.
In this article
Ask the right questions • Read the window label • Inspect the vehicle carefully • Take it to your mechanic
Understand that some private sellers may not want to allow you to test drive the vehicle and/or have it inspected by a mechanic, so you’ll need to decide if you’re okay with that.
Finally, if you are buying from a used car dealership, ask what part of the process you can do online or over the phone. The more paperwork you can handle virtually, the less time you’ll need to spend at the dealership.
Ask the right questions
Whether you’re dealing with a private seller or a used car dealership, asking these basic questions can help you decide if it’s worth the trip to take a closer look at the vehicle.
How many miles has? If the miles are more than 20,000 per year or less than 5,000, ask why. A high-mileage car used on a long road trip may have less wear and tear than if you made a lot of short trips or stop-and-go driving. Still, take any claim that “these were all highway miles” with a bit of skepticism. Additionally, while low mileage is good, it does not guarantee proper care.
¿How is it equipped? Whether they appear in the ad or not, ask about key features: transmission type, safety equipment, audio system, cruise control, power seats, Bluetooth, rear entertainment screens, rearview camera and navigation. A double check could produce some revealing discoveries.
¿What is the condition of the car? Start broadly and don’t interrupt: the salesperson might mention something you wouldn’t have thought to ask.
¿How about the body and interior? If these areas were not covered before, ask about them specifically.
¿Have you been involved in any accident? If so, ask about the extent of the damage, the cost of repairs, and who did the work. Don’t worry about minor scratches, but think twice if a car has been in a serious collision.
¿Do you have service records? You want a car that has been well cared for. Maintenance should have been performed at the intervals specified by the manufacturer. Request receipts for any parts that have been replaced. Invoices from repair shops usually indicate the odometer reading, which helps you verify the history.
¿Are there open withdrawals? Check to see if any safety removal work needs to be done on any part of the car. Dealers can access recall history, but with the VIN, you can check the manufacturer’s website or the National Highway Traffic Safety Administration website. Record the mileage when the work was performed. For more information, visit CR’s Car Recall Tracker.
Questions for private sellers
Have you had it since it was new? You want to be able to reconstruct the car’s service history. You should be skeptical if the owner claims to have performed maintenance but can’t produce a receipt, or if the car has changed owners several times in a few years. A vehicle history report can shed more light on those issues.
Are you the person who drove it the most? The ideal would be to meet the main driver or drivers of the car to see if you consider them responsible.
¿Why are you selling the car? Look for a plausible explanation rather than an interesting story. If the answer sounds evasive, be careful.
Read the window label
The Federal Trade Commission (FCC) requires auto dealers to post a buyer’s guide on every used vehicle offered for sale. Typically posted on a window, you should find certain information, including whether the vehicle is being sold “as is” or with a warranty, and what percentage of repair costs (if any) the dealer is obligated to pay. The information in the guide supersedes any contrary provision in your sales contract. In other words, if the guide says the vehicle is covered by a warranty, the dealer must honor that warranty. If any changes in coverage are negotiated, the guide should be amended to reflect this prior to the sale.
If a sale is designated “as is,” it means that the dealer makes no guarantees about the condition of the vehicle, so any problems that arise after you have made the purchase will be your responsibility. Many states do not allow “as is” sales of vehicles that sell for more than a certain price.
Inspect the vehicle carefully
No matter who you buy it from, you should always inspect the car thoroughly and take it to a mechanic for a complete inspection. Dress in old clothes that you don’t mind getting dirty and give the car a good service.
Do your inspection in daylight on a dry day, because light reflections can make cars look shiny and hide body defects. The car must be parked on a level surface and must not have been driven for at least one hour prior to the inspection.
Abroad
Body condition: Check each panel and the roof for scratches, dents and rust. Watch out for misaligned panels or large gaps, which may indicate sloppy factory assembly or a shoddy repair. Paint color and finish must be the same on all body panels.
If you think a dent may have been repaired, place a small magnet. The magnet will not stick to an area with body putty. If other parts of the car have been repainted, there may be paint stuck to the rubber seals around the hood and trunk lid.
Rust is a concern, so check the body for blistered paint or visible rust. Check the wheel arches, under-door panels and the bottom of the doors.
Open and close each door, the hood and the trunk. Gently lift and release each door, especially the driver’s door. If the hinges appear to be loose, the cart has had heavy or prolonged use. Inspect the rubber seals to see if they are broken or rotted.
Glass: Look carefully at the glass to make sure there are no cracks or large pitted areas. A small stone chip may not be cause for alarm, although you should mention it in negotiations. But windshield cracks will get worse and lead to an expensive repair.
Suspension: Walk around the car to see if it is level. Push down on each corner. If the shock absorbers are in good condition, the car should bounce only once, not bounce up and down. Grab the top of each front tire and pull it back and forth. If you hear a metallic noise, your wheel bearings or suspension joints may be damaged.
Lights and lenses: Ask a friend to confirm that all the lights are working. Make sure all lenses and light reflectors are intact and not cracked, fogged by moisture, or missing.
Tires: A lot is known about tires. A car with less than, say, 20,000 miles should probably still have its original tires. Be careful with a low mileage car with new tires and check that all four tires are the same. If the car has different brands of tires, ask why they were replaced.
Tread wear should be uniform across its width, and the same on the tires on the left and right sides of the car. Ask if the tires have been rotated periodically. Otherwise, wear is usually more severe on the drive wheels.
Aggressive drivers tend to wear a lot of the outer edge of the front tires, at the edge of the sidewall. Assume the car has been driven hard if that area shows increased wear.
Tires that have been driven overinflated tend to wear more in the middle than on the sides. Chronically underinflated tires show more wear on the sides. Cupped tires (those worn unevenly across the circumference of the tread) can be a sign of a problem with the steering, suspension, or brakes.
Additionally, they must have at least 1/16 of an inch of tread to be legal. Check the tread depth with a tread depth tool, available at auto parts stores, or with a quarter. Insert the coin into the tread slot, with Washington’s head facing down. If you can see the top of its head, the tire should be replaced.
Examine the sidewalls for scratches, cracks or bulges, and look for dents or cracks on each wheel. Check that the spare part is in good condition and that it has the appropriate jack and wrench.
Inside
The interior of a car may be the most important thing to you because it is where you will spend the most time while you own it. So take your time and take a full look.
Smell: When you open the car door for the first time, smell the inside. A musty or moldy smell could indicate water leaks. Remove the mats and check for moisture stains. A pungent odor may indicate that the car was used by a smoker. Check the lighter and ashtray (if you have them) for evidence. Some odors, such as mold and smoke, can be very difficult to remove.
Seating: Try all the seats, even if you probably won’t sit in the back of the car. The upholstery should not be torn or badly worn, especially on a low mileage car. Check all seat adjustments to make sure they work correctly and that you can find a good driving position. Make sure all settings work in both the driver and passenger seats.
Don’t forget the back! Even if you don’t plan to sit there regularly, test each seating position to look for lumps in the padding or uneven support. If the seats can be folded, make sure the lowering mechanism works.
Pedals: The rubber on the brake, clutch and accelerator pedals gives an indication of use. A car with few m illas should not show much wear. Pedal rubber worn in places (or new) indicates that the car has been driven a lot.
Buttons and controls: Turn on the ignition switch without starting the engine. You should make sure that all warning lights, including the check engine light, come on for a few seconds and go off when you start the engine. Check to see if the engine starts hard when cold and idles smoothly. Then test each switch, button and lever.
With the engine running, turn the heater on full blast to see how hot it gets and how quickly. Also turn on the air conditioning and make sure it cools down quickly.
Sound system: Check reception on AM, FM and satellite radio. If the car still has a CD player, try loading and ejecting a disc. Bring your smartphone or MP3 player and connect via Bluetooth or cable. Check if the car has wireless connectivity with Android Auto and Apple CarPlay.
Ceiling: Check the headliner and crown molding for stains or sagging to see if water is leaking through doors or windows that don’t fit properly. Check that the sunroof or moonroof opens and closes properly and seals well when closed. Inspect the convertible top for tears by shining a flashlight on it.
Trunk: Use both your nose and eyes. Smell and look for signs of water entry. See if the carpet feels wet or smells musty, and check the spare tire well for water or rust.
Under the hood: engine-related components
It is best to carry out these checks with the engine cold. First inspect the general condition of the engine compartment. Dirt and dust are normal, but be careful if you see oil splashed on the pavement. You should also keep an eye out for a battery covered in corrosion or loose cables and hoses.
Hoses and straps: Tighten the various rubber hoses that go to the radiator, air conditioning and other parts. The rubber should be firm and flexible, not rock-hard, cracked or soft. Feel the drive belts to determine if they are frayed.
Liquids: Your owner’s manual will tell you where to look to check all fluid levels. Engine oil should be dark brown or black, but not sandy. If the oil is honey-colored, it has just been changed. If the dipstick has water droplets or shows gray or foamy oil, it could indicate a cracked engine block or a blown head gasket, two serious problems.
Check the automatic transmission fluid with the engine warm and running. On some cars, the dipstick has two sets of marks to check whether the engine is hot or cold.
The transmission fluid should be pink, not brown, and smell like oil, without a “burning” smell. The dipstick should not leave visible metal particles on the rag, another sign of a serious problem. Brake and power steering fluids must be within the safe zone.
Radiator: Look inside the plastic reservoir that is connected by a rubber hose to the radiator. The coolant should be greenish or orange, not milky or rusty. Greenish stains on the outside of the radiator are a sure sign of leaks.
Battery: Some “maintenance-free” ones have a built-in charge indicator: green usually means the battery is in good condition and yellow or black usually means the battery is running low. These reveal the status of a single cell and may not give an accurate reading about the status of the entire battery. If the battery has filler caps, wipe the top with a rag and then carefully lift or unscrew the caps to observe the fluid level. A low level may mean that the battery has been working too hard. Any competent mechanic can check the charging system and perform a test of how it charges the battery.
Electric and hybrid vehicles: Make sure the battery is fully charged before a test drive so you can see its projected range. On hybrids, check the car’s display to make sure the battery is charging and discharging as you drive.
under the vehicle
If you can find the spot where the car is usually parked, look for marks from old puddles of gasoline, oil, coolant, or transmission fluid. The clear water dripping under the car on a hot day is probably just water condensed from the air conditioning.
Exhaust pipe: Feel for residue. If it is black and greasy, it means there is burnt oil. The tailpipe stain should be dry and dark gray. Although some rust is normal, severe rust could mean the car needs a new exhaust system.
Below: If the car is tall enough to slide under, you may be able to do some basic checks. Spread an old blanket on the floor and look under the engine with a flashlight. If you see drops of oil, oil leaks, or green or red fluid on the engine or on the pavement under the car, it is not a good sign.
Examine the constant velocity joint boots, which are the round black rubber bellows at the ends of the axle shafts. If they are cracked and leaking grease, assume the car has bad CV joints, or needs another expensive repair.
Structural components with large bends and dents on the underside of the car or in the fuel tank indicate a past accident. Welding on the frame suggests that a section may have been replaced or cut away for repair work. A fresh coat of paint can hide recent structural repairs.
Take it to your mechanic
Before closing the deal, have the car inspected by a repair shop that performs routine diagnostic work. A dealer should have no problem lending you the car to have it serviced, as long as you leave identification. If a salesperson tells you that an independent inspection is not necessary because the dealership already did it, he insists that your mechanic look at it. If a private seller is reluctant to let you drive the car to a shop, offer to follow them to the inspection site.
A full diagnosis should cost between $100 and $150, but check the price in advance. Ask the mechanic for a written report detailing the condition of the car, indicating any problems found and the cost to repair them. You can then use the report when you start negotiating with the seller.
If you don’t know any repair shops, you can ask the name of a good one at a local auto parts store. If you can’t get references, look for a national used car inspection service, such as SGS or Carchex, or the Car Care Council, an industry-backed organization for the automotive aftermarket. Please note that there are no performance criteria for the stores listed on the site.
To check for complaints about a store, research the companies on the Better Business Bureau website. Members of the American Automobile Association (AAA) can use one of their recommended facilities.
If you’re going to a shop for the first time, look for certificates or window stickers from AAA or the National Institute for Automotive Service Excellence (ASE). AAA certified workshops must meet certain quality standards. The ASE awards certificates to mechanics who pass exams in any of the eight areas of specialization. The ASE does not certify stores as a whole, but if 75% of employees are ASE certified, the store can carry the seal.
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