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The top 10 car warranty claims in the UK

Warranty companies share their most common repair claims exclusively with The Car Expert

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We have written a lot about considering a used car warranty – or mechanical breakdown insurance – for when your new car’s policy runs out, or if you have bought a good used car that deserves some decent cover.

It’s definitely a consideration well worth thinking about. As cars get older and rack up more miles, their parts wear and eventually give up. It’s a fact of motoring life and a massive irritation when something in your car decides to let go, either on your driveway or, worse still, at the side of the road.

But at least if you have bought some decent warranty cover, you won’t have the anxiety of thinking about the cost of the parts and labour to get your pride and joy back up and running again.

Still not convinced? Here’s the top ten list of most common car warranty claims, supplied with the help of cover providers Warranty Direct and Click4Warranty, with a brief description of what the part does and the guide price of a replacement.

Of course, all car makes and models are different so cost of repairs will vary enormously. But this list will give you a general idea of the potential costs awaiting you to help you decide whether a warranty is right for you.

Remember a warranty policy doesn’t just take care of the cost of replacement parts. They can also cover labour fees and (depending on your level of cover) important extras such as car hire. So, for many motorists, particularly those that drive long distances or rely on their car every day, it can prove to be a smart investment.

The UK's top ten car warranty claims

The UK’s top ten car warranty claims

1. Radiator

According to our providers, there are more car warranty claims for radiator repairs or replacements than any other kind of failures.

A car’s engine generates an enormous amount of heat – more heat than power, in fact. Petrol or diesel are ignited in the cylinders, causing literally hundreds of explosions every single second. That’s a lot of heat that has be to managed, and the job of doing so falls to your radiator.

A series of small channels inside your engine, containing water or other coolant, absorb that heat and carry it back to the radiator in pipes. Fresh air flows through the radiator grilles (which is why the radiator is normally at the very front of the car), cooling the hot fluid in the radiator elements before that fluid is pumped back into the engine.

If the radiator fails, you’ll usually end up dropping coolant all over the ground and the engine will quickly overheat. That, in turn, can cause catastrophic and very expensive damage to the engine.

Guide cost to replace: £450

2. Coil springs

Springs attached between the suspension and the body of the car allow the wheels to move up and down vertically, riding over bumps and holes. That smoothes out the ride to make your journey comfortable.

The larger and heavier your car, the larger the springs need to be to absorb its weight. SUVs also tend to have bigger and heavier wheels than normal cars, which means the the car’s suspension has to control the movement of both a very heavy car and a set of heavy wheels. It’s a lot of work.

Your car’s springs contain an awful lot of energy wound up in those coils, and they have to be installed or removed with the right tools and training to prevent injury and damage. If a spring snaps on your car, it can cause an awful lot of damage to the suspension components around it.

Guide cost to replace: £200 (medium size car)

3. Fuel injectors

Injectors are part of the car’s fuel system and spray the right amount of petrol or diesel into the turning engine at the right time. They are incredibly finely tuned to deliver a few milliletres of petrol at exactly the right time – dozens of times every second – to ensure best performance but also best fuel economy.

Given that fuel injectors are so finely calibrated, it’s not surprising that they’re not cheap to replace. They can easily be damaged by any kind of detritus in your fuel system, which can happen if you run your car out of fuel. The fuel pump sucks the dregs out of the bottom of the tank and pumps it down the fuel lines to the injectors, which can get clogged and damaged.

Guide cost to replace: £350

4. Electrical system

Many components make up the electrical system, including the battery, alternator, starter motor, lights and ignition system. As such, electrical system failure covers quite a broad range of possibilities. On older cars, a failure of a key electrical component can be enough to write the car off, as the cost of repairs can easily be more than the car is worth.

Guide cost to replace: £200 – £2,000 (depending on what has failed)

5. Steering

The mechanical set up that allows the driver to control the direction of the car with only a light touch on the steering wheel. Most cars have a power steering system, which uses either hydraulics or a small electric motor to provide assistance to reduce the amount of effort needed to turn the wheel.

This is critical for modern vehicles – especially SUVs, which tend to have enormous wheels and tyres. If you’ve ever had power steering failure, you’ll realise how difficult it is to physically turn the steering wheel.

Guide cost to replace: £300 (power steering pump)

The top car warranty claims in the UK

6. Water pump

Part of the same cooling system as the radiator, the water pump keeps the cooling water (which is actually a specialised coolant, not actually water) circulating through the engine and radiator via a number of pipes and hoses.

If the pump fails, the coolant can’t move through the engine to keep it cool, and the engine will overheat in very short order.

Guide cost to replace: £150

7. Alternator

The alternator is an electrical generator that takes some of the engine’s energy and converts it to electricity to supply dozens of different systems in your car that require electrical power, such as headlights, radio, windows, mirrors and the crucial computer systems that manage the car’s operation. It also charges the car battery at the same time so that you can start your engine each day.

If it stops working, you’ll get electrical failures and a flat battery. You can jump-start the car with some cables, but the battery won’t charge so you’ll be back in the same position next time you turn off the engine.

Guide cost to replace: £450

8. Gearbox

The gearbox takes the power from your car’s engine and turns it into the forward motion of the wheels, using a series of different gears, manually or automatically. Modern gearboxes are very complicated and precise things, usually containing anywhere between six and ten gears (plus reverse). Automatic transmissions are even more complicated.

Unfortunately, gearboxes are also very expensive to repair or replace if they fail.

Guide cost to replace: £3,000

9. EGR valve

The exhaust gas recirculation (EGR) valve helps to reduce your car’s air pollution by reducing nitrogen oxide (NOx) emissions. It controls the flow of exhaust from the engine, mainly during acceleration, and can push some of the exhaust gases back into the engine to re-use them.

It’s a key bit of tech to help reduce overall pollution levels, but it’s another thing that can go wrong. If it fails, your car will start spewing out much higher levels of pollution, which will cause it to fail an MOT. It could also mean reduced performance, increased fuel consumption and stalling while idling.

Guide cost to replace: £450

10. Turbo

A turbocharger (turbo for short) is a fan that spins at very high speed to force more air and fuel into the cylinders of the engine. Depending on the type of car you have, this is used to either create more power from the engine, or to improve engine efficiency. The vast majority of new cars now have turbocharged engines for efficiency, although there is still a performance advantage as well.

Turbos spin at incredibly high speeds. Your engine will typically work at about 1,000 to 3,000 revolutions per minute (rpm). That’s 50 revolutions every second, which seems incredible. But a turbo can spin at more than 200,000 rpm, which is more than 3,000 revolutions every second. It’s mind-boggling. But working that hard means that if it breaks, it’s not going to be a minor failure and it is going to be expensive.

Guide cost to replace: £1,500

Is a used car warranty for you?

Any kind of warranty or insurance policy is a matter of balancing risk against reward. Some cars are inherently more reliable than others, although the risk of mechanical failure increases as any car gets older and covers more miles. Similarly, some mechanical failures are more expensive than others.

You could potentially drive for years, owning several different cars, without making a single warranty claim. On the other hand, you could end up with a hefty bill if something does eventually go wrong and you’re not covered.

At the bare minimum, you should spend a few minutes getting some warranty quotes for your car so you can make an informed decision. The cost of a used car warranty policy is likely to be less than the cost of any of the top ten car warranty claims listed above, so it’s very much worth considering.

Here at The Car Expert, we have some fantastic warranty offers for our readers provided by our commercial partners. If you’re interested in a used car warranty, you should check these out:

  • ALA Insurance provides used car warranties in conjunction with the RAC
  • MotorEasy offers warranties and many other types of cover for car owners
  • Warrantywise is a long-established and multi-award-winning warranty provider

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Additional reporting by Stuart Masson.

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Tom Johnston
Tom Johnstonhttp://johnstonmedia.com/
Tom Johnston was the first-ever reporter on national motoring magazine Auto Express. He went on to become that magazine’s News Editor and Assistant Editor, and has also been Motoring Correspondent for the Daily Star and contributor to the Daily and Sunday Express. Today, as a freelance writer, content creator and copy editor, Tom works with exciting and interesting websites and magazines on varied projects.