Searching for the Most Reliable Cars? 3 Things to Consider

Every internal combustion engine requires what is known as a timing system, which keeps the pistons and valve springs in perfect sync with one another. You probably don't give it much thought, but the timing system is one of the most important components in your vehicle, as mistiming will quickly lead to the pistons and valves smacking into each other inside the engine block and causing costly damage.

Most engines will use either a timing chain or belt that wraps around gears connected to the crank and camshafts. The belts and chains are both responsible for keeping everything in sync, but they each have slightly different characteristics. Timing belts are made from steel-reinforced rubber and naturally wear out over time. Usually they must be replaced every 60,000 to 100,000 miles (96,561 to 160,934 kilometers), depending on vehicle model. It's a costly operation. Mechanics have to remove many components to get into the timing system, and the belt replacement can easily run over $1,000 with labor.

Timing chains, on the other hand, are made fully from metal, and typically last the lifetime of the engine. For this reason, an engine with a chain can save thousands over several years of use. Why did manufacturers start using belts at all? A primary reason is engine noise. Rubber belts are able to operate more quietly than chattering chains, which helps eliminate noise in the cabin. But nowadays, automobile manufacturers have found ways to make chains less noisy and so timing chains are increasing in popularity, thanks to their reliability advantage.

With either timing component, the driver should keep up on regular oil changes and vehicle inspections to be sure the system will stay running smoothly. Old oil can deposit contaminants in the timing case and lead to premature wear.

The transmission is one of the most mechanically complex components in any vehicle, and it has to withstand a lot of hardship over many thousands of miles. Manual transmissions are one of the oldest gearbox designs, making them proven technology. With regular maintenance, the manual transmission can often last the life of the vehicle. However, its clutch pad will eventually need replacing, which can run a few hundred dollars. The gearbox also uses parts called synchromesh, or syncros, to keep the shifter engaging smoothly. These can wear out over several years, causing a clunky shifter which may pop out of gear until the part is replaced to the tune of $1,000.

But most cars nowadays, particularly in the U.S., use torque converter automatic transmissions, which are very durable. Auto gearboxes are built with heavy steel components and will often last hundreds of thousands of miles. To ensure this, it's important to keep up on regular inspections and automatic transmission fluid changes in order to keep the mechanism free of contaminants. On the other hand, torque converter autos are expensive to manufacture and rebuild, which can lead to thousands of dollars in repair bills if the transmission does eventually fail.

Continuously variable transmissions (CVTs) are taking over much of the new car market. They are a type of automatic transmission that is cheaper to make. They're also nominally more efficient, since they don't have to shift gears at all. Most vehicle CVTs use a rubber belt that connects the engine side and the driveshaft side of the transmission, like the previously mentioned timing belt. This belt can also be the weakest link of the system, and wear out earlier than older transmission designs. CVTs also demand more frequent fluid changes. Despite being cheaper to manufacture, a CVT rebuild can still run a driver thousands of dollars. So, in terms of reliability, a CVT and an automatic are about the same, but the CVT will have a more demanding maintenance schedule.

Electric and hybrid vehicles are seeing increased popularity in the new car market, mostly thanks to their superb fuel efficiency. In addition, they can offer a few reliability advantages when compared to traditional engine configurations.

Most hybrid and electrics today come equipped with what's called a regenerative braking system. This system essentially runs the electric motors in reverse while decelerating, or coasting downhill. The friction from the motors slows the vehicle down, while sending power back into the battery and extending electric range.

Cars with regen braking systems also have regular mechanical brakes as backup, but they only really have to use them at the last moments of coming to a stop, or during emergency hard braking. As a result, brake pads and rotors can last much longer. They can run about 45,000 miles (72,420 kilometers) before servicing, as opposed to 15,000 miles (24,140 kilometers). When a brake job can run up to $1,000 with parts and labor, that's a lot of change back in your pocket over the life of the vehicle.

Fully electric cars also require very little fluid replacements during use, since they don't require engine oil or coolant. Electric power steering and braking systems similarly run without lubrication. Likely, the only fluid that will need to be changed is the transmission oil. This will save quite a bit of time and money in the shop. Note that this reliability advantage only goes to pure EVs. Since hybrid vehicles make use of internal combustion engines, most of the conventional service intervals will still apply.

Gas engines do however have one leg up over electrified cars; their lack of expensive lithium ion batteries. These power cells will degrade over hundreds of charge cycles and see reduced range capacity. Batteries are often warrantied up to eight years and 100,000 miles (160,934 kilometers). However, replacing the unit out of warranty will rack up a considerable garage bill. Parts and labor can easily run over $5,000 for small-battery electrics and hybrids, maxing out over $10,000 for long-range EVs.

When you're at a dealership, or shooting emails to a seller, don't be afraid to ask questions about the prospective car's drivetrain components. A knowledgeable salesperson should be able to tell you if the vehicle has a timing chain, CVT or regen braking. Also, search those particular model specs online. If a common issue arises with a certain component, people will probably be raising their voices about it, especially if the model has had a few years to show those weak points. Sites like Kelley Blue Book, Consumer Reports and J.D. Power also can provide expert resources to make you more informed while shopping for a vehicle.