Like most drivers, you’re probably aware that you need to change your car’s engine oil regularly. You might also know that the cabin filter and air filter (two items that are often up-sold by repair shops) need to be swapped out upon occasion.
But there are other important maintenance items you might overlook—and that can be a problem. Skipping critical routine services can eventually lead to a breakdown, followed by a hefty repair bill.
What are the Regular Car Maintenance Items that Most People Forget?
All cars have a maintenance schedule that’s defined by the vehicle manufacturer. The schedule is listed in your owner’s manual or supplemental service booklet, making it easy to find.
Unfortunately, most drivers never crack open their owner’s manual or any of the other documents that come with their car. As a result important services, such as the ones on this list, often get overlooked.
Timing Belt Replacement
Within the last decade or so, timing belts have gradually been phased out and replaced by timing chains on most newer vehicles. But many cars on the road still have a timing belt under the hood — and if your car is one of them, replacing the belt is not something you’ll want to forget.
Unlike a car’s other belts, the timing belt is a critical internal engine component that is hidden from sight. The timing belt keeps the camshaft(s) and crankshaft in sync so that the valves open at the right point in the pistons’ travel. Timing belts require periodic replacement (unlike timing chains) because they’re made of rubber, which eventually degrades.
If your car has a timing belt, and it’s not replaced according to the vehicle manufacturer’s maintenance schedule, it may stretch or break. When that happens, the valves can collide with the pistons leading to catastrophic damage.
If your car’s engine has an interference design, its valves are likely to contact the pistons if the timing belt breaks. But even non-interference engines can potentially be damaged by valve-to-valve contact from a broken timing belt. In either scenario, your car will also stop running.
So, if your car has a timing belt, you’ll want to be sure to replace it at the recommended interval.
Most of today’s vehicles have hydraulic lifters (also known as tappets or lash adjusters) inside the engine. The hydraulic lifters use engine oil pressure to compensate for the changes in valve train clearance that occur over time.
But some vehicles on the road still have solid lifters under the hood. When solid lifters are used, the clearance between valvetrain components typically requires routine inspection (and, in some cases, adjustment). For example, some later-model Hondas and Subarus still need to have their valve clearance checked and adjusted according to the vehicle manufacturer’s maintenance schedule.
If there isn’t enough valve clearance the valves might be held open, resulting in a loss of compression and possible damage. On the other hand, if the valve clearance is excessive the engine will be noisy and the valve train will experience accelerated wear.
Fluid Exchanges Beyond Engine Oil
Engine oil isn’t the only automotive fluid that requires routine service. On almost all vehicles, the transmission fluid should also be replaced periodically. Neglecting to service the transmission fluid can lead to premature transmission failure, which is a costly problem to have.
In addition, vehicles with a rear-wheel drive-biased layout have a rear differential filled with fluid that requires replacement. Four-wheel drive and all-wheel drive vehicles also have a transfer case (or transfer unit) and, in some cases, a front differential, all of which require routine fluid exchanges.
Coolant is another fluid that requires regular service. Although most vehicles now come from the factory with long-life coolant, the built-in corrosion inhibitors still eventually break down, creating an acidic solution.
Finally, some automakers recommend routine replacement of the power steering fluid (if equipped) and brake fluid. Check the service schedule for your vehicle to determine which fluids should be changed and when.
Fuel Filter Replacement
Most newer vehicles now have a returnless fuel system and an in-tank (non-serviceable) fuel filter. However, if your vehicle is over a decade old, there’s a chance it has a serviceable fuel filter mounted outside the tank.
Serviceable fuel filters must be replaced periodically. Otherwise, your vehicle can suffer from problems, such as rough running, poor acceleration, and (in extreme cases) a no-start condition. So, if your car has a serviceable fuel filter, you’ll want to be sure to replace it at the correct interval.
Spark Plug Replacement
Unless you drive a diesel-powered vehicle or a purely electric vehicle, your car has spark plugs that require periodic replacement. Even though today’s vehicles often have spark plugs that last upwards of 100,000 miles, routine service is still necessary.
Failing to replace your car’s spark plugs on time can result in an engine misfire, which, if left unchecked, can damage the catalytic converter and other costly components. In some extreme cases, a worn-out spark plug’s ground electrode can even break off, falling into the engine and causing catastrophic damage.
Remember to Follow the Manufacturer’s Maintenance Schedule
In the end, it’s all about following the vehicle manufacturer’s maintenance schedule for your car. The schedule tells you exactly what services are due and when so that there’s no guesswork.
With that in mind, now’s the time to dust off your owner’s manual and related documents to get yourself up to speed.
Any information provided on this Website is for informational purposes only and is not intended to replace consultation with a professional mechanic. The accuracy and timeliness of the information may change from the time of publication.