9 March 2016

Basic car maintenance part two: tyres, battery, bodywork and brakes

Last week on The Root we posted part one of our car maintenance series, with advice on how to check and top up coolant and screenwash, steps to make sure a car’s lights are working and guidance on monitoring and topping up engine oil. This time around, the focus is on tyres, batteries, bodywork and brakes.


These four black circles form you and your car’s only contact with the road, which is a humbling thought, so it’s important to check them at least once a month.

Tyre pressure – why it matters

  • Incorrect pressure can dangerously reduce grip and increase stopping distance
  • Tyres can become damaged and wear out more quickly if inflated incorrectly
  • A car’s fuel consumption can also be negatively affected, costing you more in petrol or diesel
  • Especially needs checking before motorway journeys
Carrot Insurance telematics young drivers blog - basic car maintenance - tyre pressure


How to check tyre pressure

  • Use a handheld, old-fashioned pressure gauge, portable inflator or an air machine at a petrol station
  • Your car’s user manual should tell you the pressures, which are commonly also displayed on a sticker inside the driver’s door or on the back of the fuel filler cap
  • Front tyre pressures are often higher than rear, because of the extra weight of the engine at the front
  • Most manufacturers recommend higher pressures for heavily loaded cars e.g. carrying passengers and luggage
  • Don’t inflate or deflate your tyres when they are warm. If you don’t have a portable inflator, head to the nearest petrol station
  • A regular drop in the pressure of a particular tyre usually indicates a slow puncture, so take your car to a garage as soon as you can, driving slowly on the way there if you’re not able to fit a spare in the meantime
  • Top tip: if you don’t have any change in your wallet or purse, the air machines at Sainsbury’s filling stations are usually free of charge to use. Just don’t be surprised if there’s a queue.

Tyre tread depth and wear – what you need to know

Driving with tyres that are unevenly worn, below the legal tread depth limit or damaged in another way could result in your insurance being invalidated, a police fine of upto £2,500 and 3 penalty points being imposed, plus you or someone else could end up as a road safety statistic.

  • It’s best if all four tyres are the same brand, pattern/type and age
  • They mustn’t have any tears, bulges, lumps or other damage
  • If you can see the ‘cord’ or ‘ply’ strands deep below the rubber surface, it’s highly dangerous
  • The minimum legal tyre tread depth in the UK and Europe is 1.6mm
  • This must be “throughout a continuous band in the centre 3/4 of the tread and around the entire circumference”, to quote the rulebook
  • ‘Part worn’ tyres may be cheaper but they can pose a safety risk.
Carrot Insurance telematics young drivers blog - basic car maintenance - TTD


How to check tyre tread depth

  • Only inspect your tyres when it’s safe to do so
  • Measuring tyre tread depth only takes a couple of minutes
  • Old-fashioned or more modern digital tyre tread depth gauges can be bought cheaply in car parts shops, supermarkets and online
  • If you don’t have access to any type of gauge, use a 20p coin. Slot the coin into one of a tyre’s main grooves. The outer rim of the 20p coin should be hidden inside the tyre groove. If you can see any of the coin’s outer rim, the tyre tread depth is low
  • Your tyres will probably have little ‘indicator blocks’ moulded into the grooves. These markers sit lower than the grooves, meaning that when the surface of a tyre has been worn down to the marker, the tyre must be replaced urgently. 

Other good tyre advice

  • When a professional at a garage or from a mobile tyre fitting business puts one or more new tyres on your car, they should also do something called ‘balancing’, which means adding weights to your wheel to help keep the tyres in good condition, everything working nice and evenly
  • If you can afford it, taking your car for a full four-wheel laser wheel alignment or ‘geometry’ check is often well worth the money, getting rid of any vibrations and wobbles and helping keep your car as fuel efficient and straight as possible. Full 3D alignment typically costs around £150 and is best done on machines like a Hunter or John Bean, which you can ask about in advance
  • If you are concerned about a slow puncture, tyre wear or any other issue, ‘fast-fit’ garages can be found in most towns and they’re usually happy to inspect tyres free of charge and can sometimes repair a puncture using a kit, for a fee of around £30.
Carrot Insurance telematics young drivers blog - basic car maintenance - wheel alignment


All kinds of symptoms can result from a car battery that is reaching the end of its life, from the car failing to start in the first place, to dashboard lights intermittently going dim. Car batteries are generally said to last upto around five years before they need replacing. Battery drain can affect any car from time to time and finding someone with jump leads who can help start your car may well be enough to avoid any further issues.

Carrot Insurance telematics young drivers blog - basic car maintenance battery


Some useful battery facts and tips

  • Remember to switch your car’s lights, stereo and everything else off when you park up, as this is a common cause of battery problems
  • Checking your battery before cold weather is really sensible, as they require more charge to start cars in such conditions
  • Lots of short journeys can kill a battery early, so it’s best to make some longer journeys once in a while
  • If your battery’s connection terminals look corroded or you can see any gunk, grease or powder forming anywhere near it, get it checked by a garage
  • If you leave your car standing for weeks between driving it, it may be sensible to purchase a cheap home battery charger
  • People confident enough to replace a car battery themselves need to remember that it’s illegal to dispose of it in household waste
  • If you’re really eager, voltmeters (AKA multimetres) can be bought cheaply and used for testing battery voltage anywhere as long as the car’s parked safely
  • To measure the voltage, make sure the engine, ignition and lights are all off. Switch the voltmeter on and turn the dial to the right setting, then connect the red lead to the car battery’s red terminal, followed by the black lead
  • 12.6v is generally a sign your car’s battery is healthy, a reading of 12.2v or lower indicating that you need to get it looked at.


Keeping your car clean by having it washed from time to time doesn’t only maintain its shine – it also reduces the risk of corrosion or other unwanted effects on the bodywork.

If you notice any dents, scrapes and especially any parts that have come loose, are hanging off or are damaged in some other way, take your car to a garage as soon as possible. Parts dangling or falling from a car pose a serious road safety hazard.

Carrot Insurance telematics young drivers blog - basic car maintenance - bodywork


Suggesting that a young driver monitors and tops up their car’s brake fluid is probably a bit over-the-top, but a good habit to get into when it comes to brakes is to test them by:

  • Pressing the brake pedal before setting off, whilst the engine and handbrake are both on
  • Doing so again shortly after setting off, as long as the surrounding environment is safe
  • If the brake pedal feels spongey, significantly different, is hard to push down or feels loose, get it checked
  • Any noises that can be heard when braking, such as grinding or banging, mean it’s time to visit a garage.

We hope this second car maintenance instalment on The Root has proved useful for you as a young driver or perhaps even a parent. If you have any questions on the car maintenance topics covered in this or last week’s post, get in touch on Twitter or Facebook.

Oliver Hammond

Written by Oliver Hammond

Oliver is an established freelance motoring writer, published journalist and automotive copywriter based in Manchester. He regularly reviews cars and covers events and launches as editor of petroleumvitae.com and his articles appear in various magazines each month. No relation to Richard from Top Gear, he’s got a weakness for luxo-barges, proper 4x4s and oddball cars.