Replacing certain car parts every couple of years may seem costly or unnecessary, but these replacements can help to prevent larger mechanical issues or failures in the future.
However, knowing which car parts to replace (and when) can be a confusing ordeal – especially when there’s so much conflicting information on the internet.
Using our 70 years of experience as one of the UK’s largest car dealers, we’ve put together a list of the most common car parts, how often they should be replaced and how to recognise when they’re on their way to motor heaven.
Did you know? If you start driving at the age of 17 and stop when you’re 80, then you’ll most likely have to replace an expensive part of your car around 25 times. Considering this is over the course of 63 years, then this isn’t as bad as it sounds!
Common replacement car parts (and when they should be replaced)
Windscreen wiper blades
When will I know if there are problems with the windscreen wiper blades?
If your windscreen wiper blades become warped or damaged, then they may judder against or partially miss your windscreen.
When is it likely that I’ll need to replace the windscreen wiper blades?
When you start to notice that your windscreen wiper blades aren’t working effectively, then it’s time for a replacement. This will most likely be every six months to a year.
Headlight and rear light bulbs
When will I know if there are problems with my headlight or rear light bulbs?
You’ll either notice that your lights are dimmer than usual or not working at all.
When is it likely that I’ll need to replace the headlight and rear light bulbs?
Vibrations on the road, debris and how often you use your lights will affect how long they last. Typically, we’d recommend replacing your light bulbs every year.
Oil filter
What does an oil filter do?
The oil filter is similar to the fuel filter, but instead helps to remove contaminants from the car’s engine oil. It’s these contaminants that can cause damage to the inside of the engine.
When will I know if there are problems with the oil filter?
When the oil filter needs changing, it’s likely that the car won’t accelerate properly and ‘sputtering’ may occur – a term used to describe inconsistent speed variations caused by oil not dispersing through the filter like it should. If your oil pressure gauge drops rapidly, then this is also a cause for concern.
When is it likely that I’ll need to replace the oil filter?
For older cars, you’ll probably need to change the oil filter every time you change the oil (which should be roughly every 3,000 miles). However, this figure is closer to every 7,500 miles for a modern car.
Tyres
When will I know if there are problems with my tyres?
If cracks or bulges appear in your tyres, then this has likely been caused by over or under inflation and you’ll need to replace them. We also recommend having at least 3mm of tread depth on all tyres at all times, though the legal minimum is 1.6mm.
When is it likely that I’ll need to replace a tyre?
How often you’ll need to replace your tyres will depend on whether you keep them inflated correctly and the way you drive, but you should expect an average tyre to last up to 30,000 miles.
Want to have your tyres checked free of charge? Book your free tyre check with JCT600 today.
Spark plugs
What do the spark plugs do?
Spark plugs do exactly what they say on the tin – they ‘spark’ electricity from the ignition system to power your car.
When will I know if there are problems with the spark plugs?
If your spark plugs aren’t working efficiently, then you may notice that your car is consuming more fuel than usual due to poor combustion. Your car may also ‘hesitate’ upon acceleration and not respond as quickly as you’d expect.
When is it likely that I’ll need to replace the spark plugs?
How often you’ll need to replace your spark plugs partially depends on the type of spark plugs you have in your car. Some manufacturers recommend that you replace your spark plugs every 30,000 miles, whilst iridium or platinum plugs are said to last up to 100,000 miles.
Water pump
What does the water pump do?
Maintaining a consistent and optimum temperature for a car’s engine is essential for performance. The water pump ensures that the coolant keeps moving through the engine block and cylinder head, before reaching the radiator and flowing back to the pump.
When will I know if there are problems with the water pump?
If your water pump isn’t working efficiently or is leaking, then you may experience problems with your engine overheating and not operating properly (or at all). A warning light will usually be displayed on the dashboard.
When is it likely that I’ll need to replace the water pump?
Water pumps tend to last a similar amount of time as the cambelt, which is up to around 60,000 miles. By regularly changing the water pump coolant and topping the engine up with oil, you’ll greatly extend its lifespan.
Clutch
What does the clutch do?
Within a manual car, changing gears requires disrupting the power from the engine to the transmission. This is because when your car is switched on, the engine is constantly turning, meaning the wheels would always be in motion if it wasn’t for a source of friction. This is where the clutch comes in.
When will I know if there are problems with the clutch?
If you start to notice the clutch slipping a lot or difficulties in changing gear, then you may need a replacement clutch.
When is it likely that I’ll need to replace the clutch?
General wear and tear of the clutch depends on how often you drive and shift between different gears, but you’ll usually need to replace it around every 60,000 miles.
Cambelt (or timing belt)
What does the cambelt do?
The cambelt (also known as the timing belt) helps to keep the pistons and crankcase at the bottom of the engine in sync with the cylinder head and valves at the top.
When will I know if there are problems with the cambelt?
One of the most obvious indicators of a worn or loose cambelt is a squealing or rumbling sound when the engine is first started. If the cambelt is badly damaged, then your engine may even fail to start.
When is it likely that I’ll need to replace the cambelt?
It’s recommended that you replace your cambelt up to every 60,000 miles. If you want to extend the life of your cambelt, then keeping your car in the garage will help to lessen temperature fluctuations that can cause the rubber to expand and contract.
Flywheel
What does the flywheel do?
Making up part of the clutch alongside the clutch plate and pressure plate, the flywheel (often made of heavy steel or carbon fibre) is a large disc that’s attached to the crankshaft at the rear of the engine. Its role is largely to store rotational energy to keep the engine in consistent motion.
When will I know if there are problems with the flywheel?
If the teeth of the flywheel are shaved off or damaged in some way, then this can cause problems like loose spinning (this will resemble the sound of a drill) or grinding against the starter gear. The clutch may also slip more than usual.
When is it likely that I’ll need to replace the flywheel?
It’s recommended that you change the flywheel every time you need to change the clutch, which is roughly every 60,000 miles.
Fuel filter
What does a fuel filter do?
The fuel filter is designed to stop any ‘nasties’ from reaching your car’s engine. For petrol engines, these are things like impurities and debris, whilst the fuel filter for diesel engines helps to prevent water from building up and corroding the interior.
When will I know if there are problems with the fuel filter?
Initially, you may experience poor fuel mileage, followed by struggles with starting the engine or maintaining power. The ‘Check Engine’ warning light may also be illuminated.
When is it likely that I’ll need to replace the fuel filter?
With most modern cars, you’ll probably need to replace the fuel filter every 60,000 to 90,000 miles.
Brake pads
What do car brake pads do?
Most of us will know that brake pads help to slow down or stop a car abruptly, but the actual mechanisms are a little more complex. When pressure is applied on the brake pedal, hydraulic fluid in the calliper pushes the brake pads for each wheel against the rotating brake discs, resulting in the necessary friction needed to brake.
When will I know if there are problems with the brake pads?
Many cars are equipped with brake pad sensors that will indicate when the brake pads need replacing on your dashboard. If you don’t have this, then you’ll be able to tell if something’s wrong when the car starts to feel as if it’s pulling to one side or if there are grinding noises or vibrating sensations when using the brakes.
When is it likely that I’ll need to replace the brake pads?
How often you’ll need to replace the brake pads largely depends on general use and how often you’re stopping and starting at junctions or traffic lights. However, this tends to be up to every 70,000 miles (or roughly every five years).
Alternator
What does the alternator do?
Making up the automotive charging system consisting of the battery and voltage regulator, the alternator converts mechanical energy into electrical energy to power the engine, headlights, heater and more.
When will I know if there are problems with the alternator?
Most modern cars will display a warning light when there’s an issue with the alternator. However, any noticeable changes in electrical output, such as dimmed or flickering lights, may also indicate a problem. If this is coupled with growling or whining noises, then this could mean that the pulley or bearings attached to the alternator are wearing or misaligned.
When is it likely that I’ll need to replace the alternator?
Alternators typically last around seven years, or roughly up to 150,000 miles.
Car battery
What does the car battery do?
Fully rechargeable, the car battery supplies power to the car by feeding the starter and starting the engine (but we’re sure you already knew that!).
When will I know if there are problems with the car battery?
If you crank the engine but it doesn’t start – or if the engine doesn’t crank at all – then this is a probable sign that there’s something wrong with your car battery. You may also notice pale blue or white rust appearing on parts of the battery exterior.
When is it likely that I’ll need to replace the car battery?
On average, most car batteries will last up to seven years with regular use. The more frequently the car is driven and the longer the battery is kept fully charged, then the better the overall battery life will be. Car batteries also tend to last longer in cooler climates (which is good news for us Brits).
Head gasket
What do head gaskets do?
The head gasket plays a critical role within the functioning of a car’s engine. Sitting between the cylinder head and the block, it seals the oilways and waterways from the cylinders so that oil and coolant can circulate freely in the engine.
When will I know if there are problems with the head gasket?
Since head gaskets are under a considerable amount of pressure within the engine, they’re the most likely to fail and need replacing. White tinted smoke coming from the exhaust pipe and overheating under the bonnet are signs that your head gasket may have blown.
When is it likely that I’ll need to replace the head gasket?
So long as you look after your engine and cooling system, then you can expect the head gasket to last up to 200,000 miles in a modern car.
How often should I have my car serviced?
When it comes to buying replacement car parts, it’s recommended that you don’t try to change them yourself (unless it’s something simple like a windscreen wiper blade or headlight bulb). If a replacement car part is fitted incorrectly, then this will cost you more time and money in the future. Therefore, we recommend that you have your car serviced on an annual basis, so that any critical issues can be found and dealt with properly.
As a JCT600 customer, you’ll benefit from a replacement vehicle whilst we service your car, which can take anything from one to four hours. We’ll also notify you when your next service appointment is due. If you’re interested in booking an MOT, then you can find out more about our servicing and repairs here.
