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Tips For Buying a High Mileage Used Car

3821 Views 0 Replies 1 Participant Last post by  Nuffah Sparks

Buying a used car is a lot more complicated than buying a new one. You can quickly judge a car’s life by looking at its odometer, however, there are numerous other things to look out for when buying a second hand vehicle; especially one with high mileage.
While most issues can be identified by a trusty mechanic for a pre-purchase inspection, they can take time and unless your mechanic is a friend, they’ll charge for the service too. Here are a few things you can do yourself to identify some big problems.

One of the biggest worries about a high-mileage vehicle is the odometer rollback. This is where the seller rolls back the odometer of the car indicating a lower mileage than the car really has. This is especially worrisome for cars that already have high-mileage because the vehicle in question could potentially have an incredibly high number of miles on it.
Some argue that digital odometers have helped reduce the risk of odometer rollback, but that’s not necessarily true.
“It still does happen but it is risky because Carfax and CarProof all record mileage now,” Said Lou Trottier, Technician and Owner of All About Imports. “The paper trail wins in this case because it keeps people honest by fear of getting caught.”
According to Trottier, the biggest asset when buying a high mileage vehicle is getting the right papers. Asking for a Carfax or service booklet and looking at the mileage of the vehicle during its maintenance intervals can be a great help.
“If a used car has all the service history and owner history, that’s a huge bonus,” said Trottier. If you have these, it should help put you at ease. Service history can help identify if oil change intervals were performed on time, and what type of oil was used. A properly cared for car should last longer than one which has a spotty service history, so make sure to look for gaps of time or mileage when servicing, or when oil changes were performed.

Another important aspect of buying a used car is rust. Although rust is a scary and potentially dangerous problem, it’s one of the easier things to notice when looking at a used car.
“If a car has original paint then rust will obviously be showing through either bubbling just under the surface or complete perforation,” said Trottier. He explained that it’s more important to look for original paint, and while some sellers try to hide rust, a bad job can really stand out. Generally hasty paint jobs will show up a different shade, and should be easily noticeable. Another tip-off is if the outside of an old car looks like it just rolled off the lot. As they say, if it looks too good to be true, it is.
A trickier area of a high-mileage vehicle is the suspension. An abused, or worn out suspension is harder to point out without doing a pre-purchase inspection. The best you can do is to go out on a test drive and listen carefully for noises that can hint at a number of things.

Compression tests can help identify whether or not a car’s engine is performing optimally, and if anything is wrong internally. Not really something you can do yourself, unless you have the right tool. In a compression test, a mechanic will put a compression gauge in place of a spark plug and then crank over the engine until it does five or so revolutions. The mechanic will then record the gauge’s reading (in PSI) and move on to the next cylinder.
“We are looking for consistency between the cylinders,” Trottier said. Compression readings between cylinders shouldn’t fluctuate more than 25 PSI, and Trottier mentioned that ideally every one should be within 15 PSI.
He explained that while compression tests are useful, there’s just as much useful information in a test drive. “Any engine that has slightly low compression will cause the car to missfire slightly and I can feel that on a test drive.”
Low compression can indicate a bad exhaust valve, head gasket leak or if an entire engine needs to be overhauled.

A bigger concern for Trottier, and one that’s easier to observe, is if a high-mileage vehicle is burning oil.
“With the thin oil and extra-long service intervals we get a lot of cars that have carbon-ed up and seized oil control rings,” Trottier said. “Most sellers do not think to check their oil level at time of sale. I can’t tell you how many cars come in for a pre purchase inspection and I pull the dip stick only to find next to no oil showing.”
For manual transmission cars, also play attention to the clutch, and the clutch pedal. A worn clutch can be a costly repair both in regards to labor and parts, so Lou looks carefully for any signs of improper wear.
“I always check the left side of the clutch pedal for wear,” he said. “This tells me if the previous owner rested their foot on the clutch pedal and not on the dead pedal like they are supposed to”
It’s simple enough that even a non-car person can identify and pay more attention to when it comes to a test drive. “I regularly see clutch pedals with a lot of wear and this tells me to pay more attention to clutch operation,” Trottier said.

A car’s interior can also tell quite a lot about its age. Wear and tear on the seats can expose potential odometer rollback, so pay attention to the condition of the car’s interior.
Other areas to note come straight out of the used-car buying handbook. Take a look at things like rust on rotors. A car sitting at a dealership can accumulate rusty rotors. It’s often overlooked, but these can cause headaches for buyers, who will have to deal with vibrations, squeaks, squeals and possibly even a the purchase of some new rotors not long down the road.
Also watch out for brand new brakes as sometimes a dealer may try to hide a car’s shortcomings. “If the dealer does put new brakes into the car they are going to put the cheapest parts available which means lots of noises and premature wear,” explained Trottier. “I deal with this all the time. Someone buys a car and within one year we are replacing all the brakes with factory parts because the new owner cannot live with all the squeaks and noises.

Additionally, take a look at the tires of any second hand car you’re interested in. Tires that are older than six years should be replaced, and take extra care to look for any cracks in the tire’s sidewall. As for gauging the amount of tread left, it’s not an exact science, especially if the tires are low rolling resistance or high-performance models that don’t offer a lot of tread depth to begin with. Look for uneven wear, checking particularly if some of the tread blocks appear to be glazed over.
Also look for punctures and previous repairs, though a repair job isn’t necessarily a sign that you should stay away or replace the tires. Some punctures may affect the longevity of a tire. “A large nail puncture may create a weak spot and the tire will be prone to a premature belt shift.” Trottier said.

Finally, with any second hand car pay attention to any exhaust smoke that occurs when you turn the car on. Any smoke is pretty much a no-go area of any kind. Blue smoke is a product of excessive oil burning, which indicates an engine problem. Black smoke means there’s a fuel system problem, which is producing excessive unburned fuel. White smoke comes thanks to burning anti-freeze, which could indicate a head gasket failure.
It’s not easy to search for a car, and adding the many unpredictable variables associated with a second hand car can make things even more stressful. If a good looking deal on a car is stumping you with its high-mileage, try looking it over yourself. And even if the items mentioned above check out, consider a pre-purchase inspection from a mechanic or shop you trust.
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