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Make sure you recognise the red flags of a faulty used car. 

Best4 Warranty's Used Car Checklist

  • 24 May 2021

Buying a used car isn’t as mysterious as it once has been. Nowadays buyers can get a full track record (including MOT and Servicing history) before making the commitment of buying a big-ticket item such as a car.

Needless to say, there are still risks that come, whether you’re making a purchase from a main or an independent dealership. Using Best4 Warranty’s Used Car Checklist, you can educate yourself and potentially minimise any risk surrounding your purchase.

When buying a car, follow the facts and don’t be blinded by the dazzle of your dream car. It may look dreamy from the exterior but follow the cold hard facts of its history when it comes to the mechanical and electrical elements.


Check the engine

Maintenance of the engine is essential. Without a well-maintained engine can cause the owner unlimited problems with no consideration if you can afford it or not.


There are many different liquids that are put in a car to help it run smoothly, a very well-maintained car should not have this fluid leak onto the road or out of the car.

Top tips:

  • Make sure to check under the car where it’s been parked to check for an oil leak
  • Oil leaks in the engine are generally brown or black
  • Coolant (or antifreeze) can be green, prink or yellow
  • Gearbox and power steering fluid is red/brown
  • Gearbox fluid is thick and power steering is a thinner liquid


Check the dipstick is reading at the correct amount as well as taking note of the oil colour (if the oil is discoloured or a different consistency than usual, this could indicate to a poorly maintained and serviced car)

Head Gasket

This part of the engine prevents the coolant entering the engines cylinders by sitting in the between the lower and upper part of the engine.

You’ll be able to tell if the head gasket as blown because it would have begun to leak, creating a knock-on effect of a smoky exhaust, loss of power, a rough sounding engine or total engine failure.

Top Tip:

  • If you open the cap of the head gasket and find a mayonnaise-y consistency, the head gasket has blown. Walk away from the car.


When viewing the car, make sure to check the exhaust smoke colour

Top Tip:

  • Blue smoke = burning oil
  • Excessive white smoke = head gasket failure
  • Black smoke = engine burning too much fuel

Gearbox and Clutch

The checks on the gearbox and clutch are less visual than other checks. By testing out how the car drives will be the only way find any faults.

To note when testing:

  • The biting point
  • How easily it is to change gear
  • Resistance or grinding

Any abnormalities will result in a costly fix price, so ensure to examine the car thoroughly.

Exterior Bodywork Checks

When checking the outside of the car, you’re keeping an eye out for any indication that the car has been repainted or parts have been replaced. This could be a sign the car has been in an accident.

Minor bumps and scratches will not affect the performance of the car however an excessive amount could be an indicator of how well the car has been taken care of.

Keep an eye out for rust on the car, which starts as bubbling under the paint.

Wheels and Tyres

As part of the checks of the exterior, don’t forget to take a look at all 4 of the tyres (and the spare wheel).

Small bumps and grazes aren’t a serious problem, however huge and obvious dents in the rims will need replacing.

The tyres should have none of the following, as will need replacing:

  • Cuts
  • Splits
  • Gouges
  • Bulges
  • Uneven tyre wear (one side more worn than the other)
  • Excessively worn around the middle

Interior Checks

If there are tears and rips in the material, this could be a prime opportunity to haggle to price down. This is also a great time to check all the electrics on the inside are workings (lights, windows, sunroof, radio and central locking system). 


Check if the boot’s carpet is dry, otherwise this could be an indication of a leak. It’s a good idea here, to check the backseat folding mechanism works.

You can also see the car’s spare wheel, or lack of, when having a look.

Take It For A Spin

Once you’ve check out the entire car and it’s looking good, the next stage is taking it for a test drive. Testing the car’s capability at different speeds is a great way to find any noises or problems you couldn’t have heard when it was static.

The Documentation

Receiving all the documents of the car’s history, can give you a clear idea of how well the car has been kept as well as being a point of evidence to check the mileage.

The service book can show you who and when the car has been serviced previously.

You should also check at previous MOT certifications and have a look at the mileage here too. The mileage should increase by a consistent amount. If the mileage ever decreases, the car could have been ‘clocked’, an illegal practice of winding back the mileometer.


Stick to the checklist, and you’ll leave the dealership with a quality used car.

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