Little Helpers For Car Tyres

In many respects, modern cars are computers riding on tyres. Much of what happens below decks may seem to be under the driver’s control but in fact, computerised assistance is ever-present and sometimes, the computers take over. Here, we can take a look at some computer-controlled elements that specifically relate to the work of car tyres. We’ll find ourselves knee deep in acronyms but don’t worry, each will be explained.

Lets start with ABS. Which is? The Anti-lock Braking System. ABS first appeared in 1929, when Gabriel Voisin, a French aircraft and car engineer, developed a working system for aeroplanes. In the production car world, Chrysler later teamed up with Bendix to produce ‘Sure Brake’. This, a fully computerised all-wheel ABS system was available on the 1971 Imperial. Not to be outdone, General Motors stopped car tyres skidding with ‘Trackmaster’, a rear-wheel only system that first appeared on their 1971 models.

So how does ABS help car tyres? A typical system has a central electronic control unit (ECU), a speed sensor at each wheel, and hydraulic valves within the braking system. Under hard braking, a car wheel that is rotating significantly slower than its counterparts is on the point of locking. The ECU detects this and commands the appropriate hydraulic valve to reduce the braking force at that wheel. As the wheel speeds up again, the ECU reimposes full braking force - this can happen up to 20 times per second.

What does this mean in practice? When the ABS keeps the car tyres at the point of locking but doesn’t let them lock, the car is being braked to the limit of the tyres’ adhesion. This represents maximum braking efficiency. Moreover, skidding car tyres have actually lost their grip. The driver may be applying maximum braking force and locking the wheels but braking and steering control are lost. Under the influence of ABS, it becomes possible to still steer the car around an obstacle.

Now for another acronym, which describes a system that has evolved from ABS. Electronic Stability Control, or ESC, adds two further sensors to the ABS armoury. The first, a gyroscopic sensor, can detect when the car’s direction of travel doesn’t accord with the position of the second, the steering wheel angle sensor. The ESC’s software can then apply braking force to up to three of the wheels individually. Consequently, the car tyres’ grip is used to assist in making the car travel in the direction the driver has chosen. CBC, or Cornering Brake Control, is a refinement in ESC. This system can control the ABS, telling it that the wheels on the inside of the curve being taken should be braked harder than the those on the outside. It also dictates how much additional braking force is applied.

Paradoxically, an ABS-related system can help car tyres to retain grip under acceleration. A Traction Control System, a.k.a. A TCS, detects a driven wheel that’s spinning and briefly applies braking force to allow the spinning car tyre, or tyres, to regain traction. More sophisticated TCS systems can control the throttle level simultaneously, cutting power to the spinning wheels.

As you can see, these electronic aids to safety are complicated. Different manufacturer’s calling them by alternative names further complicates the issue. For example, some call their TCS an ASR, an Anti Slip Regulator. The above is a very simplistic explanation of such systems and there are other, similar systems in use. The bottom line is that they all help a car’s tyres make maximum use of the grip they offer.

Merityre are a leading UK independent supplier of car tyres. Why not visit their website at www.merityre.co.uk and see where you can buy your next set of tyres.

Belt-Tightening For Beginners: How To Cut Motoring Costs

In the wake of the Budget, we can do our own budgeting and save money on motoring. Attending to everything from your car tyres to the way you drive can save your hard-earned cash and help you avoid a deficit of your own.

1: Check Tyres Pressures

Air is no longer free at many forecourts but checking your tyre pressures frequently can save you much more than the few pence it might cost. For a start, running car tyres at too low a pressure increases their rolling resistance. This makes the engine work harder to push the car along so fuel consumption suffers. Underinflated tyres wear out faster too.

Correct tyre pressures improve a car’s handling, road holding and braking. These checks can cut your fuel bill by 10 percent and increase your car tyres’ useful life.

A major upside of checking tyre pressures in that you can look over your car tyres at the same time. Being caught with unroadworthy tyres can attract a fine of 2,50 pounds.

2: Research Insurance Needs

The recession has increased competition in most industries. Car tyres have become cheaper but insurance premiums have become highly competitive. Shop around for the best deal and make sure you’re paying only for the insurance you need.

3: Don’t be a Drag

Correctly inflated car tyres won’t be too helpful if your car is being held back aerodynamically. Trundling around town with the windows open may be enjoyable but open windows equal aerodynamic drag. The same goes for a roof rack, which can impose a surprisingly high amount of drag, even if unloaded. So, remove the rack when it’s empty. Also, tidy out your car. Carrying anything you don’t need costs fuel.

Air-conditioning also saps power; switching it off unless you actually need it saves fuel. That said, aircon is a more efficient cooling medium than open windows at above town speeds. It’s a question of balance.

4: No Short Trips

Cars run inefficiently when cold. Even the most efficient can return single fuel consumption figures for a surprisingly long time when cold. So, try to use your car only when you know it will warm up fully. The same aspects apply when warming your car, particularly on cold mornings. Drive off as soon as you start the engine - a car engine running at tickover from cold uses a lot of fuel, warms more slowly and can suffer more wear. Here, the car tyres make no difference!

5: Plan Your Journey

Longer routes, stop-start driving, unnecessary mileage and diversions all have a negative effect on fuel consumption. Use the Internet, the radio, TV and your satnav to plan your journey. Avoid rush hour traffic jams, steer clear of roadworks or accidents, and try to use motorways wherever possible. Bear in mind that the shortest route may not be the most efficient; more miles under your tyres can work out cheaper in some cases.

6: Observe Speed Limits

Speed limits have always been in place for public safety, even if many have also become a political issue. Remember that travelling at 60 mph costs less than travelling at 80 mph and wears tyres less. Equally, remember that fines and points on your licence also increase insurance premiums. Moreover, you generally can’t argue with a speed camera or police radar gun.

7: Drive Carefully

With a few exceptions modern cars are powerful enough to be lively but burning your car tyres’ rubber on a regular basis, though fun, can be expensive. Fifth gear can give 20 percent better fuel economy than third can, provided you don’t select it too early. Tyre-shrieking starts and lurid cornering are best left to your imagination - and they wear your car tyres out faster.

Merityre are a leading UK independent supplier of car tyres. Why not visit their website at www.merityre.co.uk and see where you can buy your next set of tyres.

Car Tyre Physics: How Car Tyres Behave Under Pressure

Car tyres obviously play a huge part in letting cars take corners. Few people consider how they do this in a scientific way but knowing about the forces at work is both interesting and educational. Why? Because understanding what’s involved and the terminology that applies can help your driving.

In road tests - particularly in track tests - cars are referred to as having understeer or its opposite characteristic, oversteer. These terms are directly related to car tyres, but what do they mean? The short, smart answer is simple: understeer means you’ll see what you’re going to hit, oversteer means you won’t. The less drastic explanation refers to the behaviour of car tyres when great demands are being on them. An understeering car’s driver will feel the need to apply more steering input to make the car go round the corner. An oversteering car’s driver will have to apply less steering input to successfully negotiate the corner. In drastic oversteer, he’d have to add counter steering, or opposite lock. Most cars understeer, for safety’s sake.

What is the science behind understeer and oversteer? Once again, it’s about car tyres; specifically, it’s about their slip angles. What are slip angles? Something that is easily understood when they’re explained to you.

Every car tyre has a contact patch, the area of its tread that’s in contact with the road surface. Imagine the tyres of a car that’s taking a corner. Each tyre will be following a path in the direction the driver is steering. Each contact patch will be following a path but it won’t be the same path the tyre’s carcass is following. This is because the tyre’s carcass deforms in response to the forces acting on it - the lateral force imposed by the weight of the car, and any forces of braking or accelerating. So, the tread in the contact patch follows a tighter curve than that the wheel/tyre combination is following. The tyre tread’s ability to deform locally also has a bearing on the slip angle. The slip angle is the difference between the two paths.

What, then, do slip angles do? In fact, they add grip, up to a point. Slip angles increase with increasing forces, speed included. As they increase, grip improves, until the car tyres begin to lose grip.

When car tyres begin to lose grip, one of three conditions results. When the slip angles of the front and rear tyres are the same, neutral steering occurs. If a car has 50/50 weight distribution and if its front and rear tyres offer identical levels of grip, it will have neutral handling. At the limits of grip, a four-wheel drift will occur; competition cars aim for these characteristics. A car in a four-wheel drift is cornering as fast as it can, nearly at the point of sliding off the track.

Should the car tyres at the front have a larger slip angle than the rear tyres have, understeer will result. As well as being more controllable, understeer can be used to scrub away excess speed on a racetrack. After the ultimate limit of grip, an understeering car will leave the track while going forwards; it can’t corner tightly enough.

What happens if the rear tyres’ slip angles are the greater? Under these circumstances, the grip of the rear tyres will be less than that of the front. The car’s tail will slide towards the outside of the corner. In extremis, the car will spin.

In practice, many aspects affect understeer and oversteer. These include which wheels drive the car forward (front, rear or all, four), the weight of the car and how it’s distributed, whether the car is accelerating, cruising or braking, and the speed and loads involved. However, this explanation gives an insight into your car tyres’ dynamic performance.

Merityre are a leading UK independent supplier of car tyres. Why not visit their website at www.merityre.co.uk and see where you can buy your next set of tyres.

Replacing Runflats With Conventional Tyres

We are receiving a number of queries from tyre dealers concerning customers who want to replace the runflat tyres fitted on their vehicles as original equipment with conventional tyres

Some people, it seems, do not like runflats, for a number of reasons; one of which is the higher price of runflats when they have to be replaced. Another reason is that the availability of runflat tyres could best be described as patchy and, when one has to be replaced, if the tyre dealer cannot supply one straight away then the motorist is stuck.

The situation is exacerbated by the confusion – in the tyre trade and among the general public – about whether or not runflat tyres that have suffered a puncture can be repaired. Take BMW, many of whose vehicles are fitted with runflats as OE, who recommends that punctured runflats are not repaired "as additional forces and wear have been incurred within the tyre whilst being driven deflated". The motorist may feel aggrieved that his runflat tyre not only costs more than conventional rubber, but also that the tyre dealer refuses to repair it, whereas if it were a conventional tyre, then it could be repaired.

However, by far the most common reason for replacing runflats with conventional tyres is not down to economics, but is the perceived quality of the ride – take a look at any online message board and, when it comes to runflats and comfort, hardly anyone has a good word to say about them.

The sidewall is stiffer on runflat tyres and, where these are fitted as OE, it forms part of the suspension, giving a harder ride, according to runflat critics. Of course, much depends on the driving style, but a typical message board comment is along the lines of "I couldn't believe the ride improvement when I got rid of the runflats". One suggestion is that fitting a non-runflat when the suspension had been set up for runflats makes the ride "wallowy" which contrasts with the original hard ride.

Whatever the reason for changing to conventional tyres, it is interesting that some motorists are willing to forgo the undoubted safety advantages of runflats. Also, as more and more cars are fitted with runflats as OE, presumably there will be more motorists wanting to switch.

For those who do decide to switch, what happens should they suffer a puncture? The tyre pressure monitoring systems – which are mandatory with runflats – will work equally well with conventional tyres, so a slow leak can be checked in time, but what if there is a sudden blowout? This is another question frequently asked on the message boards and the answers given are "carry a spare in the boot" (presumably given that there is room) or "carry a can of sealant".

INDUSTRY THOUGHTS

So much for why people want to change over from runflats, but what do the various sectors of the tyre industry, vehicle manufacturers and insurers have to say on the subject?

Back in 2005, the British Tyre Manufacturers' Association issued a statement concerning self-supporting runflat tyres (SSTs). On the subject of retro-fitting conventional tyres to SST-equipped cars, it points out that this "would remove the runflat capability, potentially leaving the driver immobile in a case of deflation and could compromise vehicle handling. It is therefore recommended to consult with the vehicle manufacturer or tyre manufacturer before replacing SSTs with conventional tyres."

Tyre manufacturers' websites have little to say about replacing runflats with conventional tyres. Most recommend replacing runflats with runflats and not mixing different runflat brands. One thing they all agree on is that runflat and conventional tyres should never be mixed on a vehicle.

Regarding the criticism of ride comfort, no doubt tyre manufacturers would argue that, in the early days of runflats, this may have been the case, but would point to the improvements in construction and materials since then, making the latest generation of runflats the most comfortable yet.

It should be remembered that the growing use of runflat tyres is because they are popular with vehicle manufacturers, not because the tyre industry wanted them. The BTMA statement suggested contacting the vehicle manufacturer, so we approached BMW, as an enthusiastic supporter of runflats, for their thoughts on changing to conventional tyres.

Their statement began by listing the reasons that they chose to utilise runflat technology in the first place, which primarily focused on driver and passenger safety and comfort. The statement went on:

"All of our vehicles that use runflat technology have their suspension and braking components set up to accommodate runflat tyres. Should you decide to change to non-runflats, it may alter the driving and handling characteristics of your vehicle. It is for this reason that this modification is not recommended by BMW as a manufacturer.

"However, it is possible to have standard tyres fitted. You will additionally need to purchase either a spare wheel with jack and brace set or a mobility kit, which can be ordered from the parts department of your nearest BMW Approved Dealership.

The illustration above shows a normal tyre deflated and on the left a run-flat tyre deflated clearly showing the additional sidewall support from the run-flat.

"Converting a vehicle from runflat tyres to conventional tyres will not invalidate its warranty, although this could give rise to a warranty claim being rejected where the fitment of conventional tyres is found to be directly attributable to the occurrence of any fault or defect."

So that's it – it can be done, but BMW doesn't recommend it.

TyreSafe statement

What about TyreSafe, the UK tyre safety group – where do they stand on this issue? We contacted them and, a few days later, a statement was released. In it, TyreSafe warns motorists that they could be compromising their own safety if they replace the run-flat tyres fitted to their vehicle with standard tyres that do not include run-flat technology.
The statement goes on: "With many motorists looking to reduce their vehicle maintenance costs, some have been tempted to economise by selecting tyres which do not incorporate the added technology and features found in run-flat tyres. By choosing these standard tyres, drivers risk significantly changing the handling characteristics of the vehicle which could increase their chances of being involved in an accident.

Stuart Jackson, Chairman, TyreSafe says "As a general rule, we would always recommend that drivers only replace run-flat tyres with a similar product. Run-flats have much stiffer sidewalls than those in traditional tyres and this is taken into account by vehicle manufacturers when they design their suspension and steering systems. By switching to tyres that do not use run-flat technology, the handling of the car can be dramatically altered and it may become unsafe, particularly during extreme manoeuvres."

In addition to the performance changes which may occur as a result of switching to non run-flat tyres, drivers can also cause themselves other problems. Run-flat tyres give drivers the ability to continue their journey for a limited time when they have no pressure in the tyre. Standard tyres cannot do this and must be changed as soon as there is a sudden loss of pressure.

SAFETY AND INSURANCE

The most powerful argument against getting rid of runflats is the safety angle. While punctures at high speeds are relatively uncommon, the results can be devastating without runflat capability. However, this is not the only safety factor, as, back in October 2006, Auto Express carried out a tyre test comparing runflats and standard tyres against each other on a wet and dry track.

A sentence in the report said that “fitting the wrong tyres to your vehicle could also invalidate your insurance”. Is this, in fact, the case? We contacted insurance giant Aviva and asked whether swapping from runflat to conventional tyres would affect a motorist’s cover.

The answer was unequivocal, with the Aviva spokesperson saying: “I can confirm that there would be no issue with a motor insurance policy purchased directly with us if a car was changed from runflat tyres to conventional tyres, with the only stipulation being that the tyre was road legal. We would only advise the client to call us so that this was noted, but there would be no additional terms imposed.”

We tried to obtain an industry-wide comment, but without success and the sensible course of action would be to check with your insurer before changing over tyres, to be on the safe side.

WHAT ABOUT RETRO-FITTING RUNFLATS?

In addition to replacing runflats with standard tyres, some NTDA members have been approached with requests to retro-fit runflats to cars that normally carry conventional tyres.

There is little information on this subject, but one thing for sure is that some sort of tyre pressure monitoring system will be needed. As you might imagine, the Royal Society for the Prevention of Accidents (RoSPA) seems to be a fan of runflat technology and it has the following to say about retro-fitting runflats:

"You should seek expert advice from your vehicle manufacturer before retro-fitting a runflat tyre if your vehicle has TPMS. As the tyre is more rigid, vehicles that have them as standard may require softer suspensions to compensate for the lost ride comfort. Guidance should also be sought from the tyre manufacturer."

Star Cars - Silver Screen Objects Of Desire, On Tyres

Who makes a movie? Usually, it’s a joint effort. In some films, however, it isn’t only the actors, director, crew and backroom staff that make the result memorable. It’s a car or cars and here are some we all know and love…

Roald Dahl and Ken Hughes scripted the 1968 film ‘Chitty Chitty Bang Bang’. Dick Van Dyck and Sally Anne Howes appeared in it but its specially-built star made it come alive. There were in fact six Chittys and not all ran on car tyres. One was the car in its dilapidated state, another appeared in all its rebuilt glory. Of the four others, the ‘hovercraft car’ is probably best remembered. This variation was lightened with aluminium copies of many of the brass parts. When the car had to be filmed suspended from a crane or helicopter during ‘flying’ sequences, its engine was removed to lighten it further.

Could you create a legend in just over seven weeks? In August 1965, US custom car builder George Barris was given a job to do. He had to produce a special car for TV and film work, as fast as possible. Luckily for him, a division of the Ford Motor Company had built a concept car ten years earlier. The Lincoln Futura made an ideal starting point. Barris fitted the 390 cubic inch (6.4 litre) V8-powered car with 15 inch cast alloy wheels, carrying Firestone Wide Oval tyres. Into the recipe went Cumming & Sander impact safety belts, a Moon aluminium gas tank, 2 Deist parachute packs with 10ft. diameter parachutes, and the ‘exhaust turbine’ was made from a five gallon paint can. If you need any further clues, the giveaway lies in the colour scheme. Threequarter inch fluorescent cerise stripes relieved the ‘Velvet Bat-Fuzz Black’ surface finish. Yes, we’ve been looking at the original 1966 Batmobile.

Now for a collection of vehicles, all but one of which set tyres to tarmac in reality. In 1969’s film ‘The Italian Job’, it wasn’t a real Lamborghini Muira that went into a river. It was a bodyshell on a crash-damaged chassis. However, when the film crew returned to pick up the pieces next day, they’d been stolen overnight!

Speaking of car tyres, the production crew got through quite a number with the Italian Job Minis. These were Mk.1 Austin Mini Cooper S cars; in the hands of stunt driving team L’Equipe Remy Julienne, they became legendary.

The film’s two E-Type Jaguars were Series One models, bought for a measly (for the time) £900 apiece. The red convertible registered 848 CRY, however, was restored and survives to this day. Michael Caine’s character’s 1961 Aston Martin DB4 convertible, scooped off its tyres by a digger, really did go down the mountainside - twice. In fact, the first take was unsatisfactory because the car was supposed to burst into flames (it didn’t because the man with the ‘explode button’ had to run for his life as the Aston plummeted towards him.) The ‘Aston Martin’ that we did see destroyed was a Lancia Flaminia 3c Cabriolet, dressed up by an excellent and obliging bodywork firm in Turin.

To close this little trip down memory lane, we can look at what is arguably the world’s most famous coach - ever. The six-wheeler that ended up with its rear tyres clawing at empty air at the close of The Italian Job was a Harrington Legionnaire. Perhaps the notion of reinforcing the cab so that the boarding Mini Coopers didn’t squash the driver was heralded with this: ‘Listen lads, I’ve got a great idea - er - er’.

Merityre are a leading UK independent supplier of car tyres. Why not visit their website at www.merityre.co.uk and see where you can buy your next set of tyres.

Rising Damp - How To Cope With Downpours And Floods

Here in the UK, 52% of our days are overcast. Rain is a given and it is frequently very heavy. Consequently, we should be used to it and there is no excuse for ignoring it. It is also a fact that even car tyres in prime condition inflated to the recommended pressures can struggle to cope, especially in particularly heavy rain and floods.

In heavy rain, you need two things, grip and visibility. Good wiper blades and a full screenwash bottle are essential. Doubling the distance to the vehicle in front is equally necessary. When the rainfall approaches biblical proportions, you could encounter standing water. Car tyres are designed to offer a grip by clearing water from the area that contacts the road surface. In extreme conditions, they can no longer sweep water away quickly enough. This can lead to a phenomenon called aquaplaning, in which the tyres skim along the surface of the water. Should this happen, you may find out the hard way.

How? Try to brake and very little will happen because the tyres have no grip; the same goes for steering control. A sudden, suspiciously light feel to the steering is an excellent clue to aquaplaning and the ‘cure’ is to gently lift off the accelerator; you will feel the tyres regaining their grip. Nobody who’s experienced it would deny that aquaplaning is frightening. Should it happen, it will quickly educate you into matching your road speed to the prevailing conditions.

Sometimes, rainfall becomes so heavy that the roads’ and their drainage systems can’t cope with it. Here, flooding is not only a risk, it is practically a certainty. The secret of coping with significant flooding is to employ forethought. ‘Look before you leap’ is a long established proverb and in many respects, it applies to flood driving. You shouldn’t attempt to drive into floodwater without knowing how deep it is. Tall 4×4s apart, modern cars have an engine air intake positioned quite low down. The snag is that water, unlike air, is incompressible. Should water enter the engine, the pistons will be stopped dead in their tracks. This will completely wreck the engine.

So, what do you do when you see floods ahead? A simple rule of thumb is that being able to see the road surface means you can see how deep the floodwater is. Assuming you can see the depth of the water, flood driving goes like this.

Drive straddling the white line. Being on the crown of the road puts you where the water is shallowest.

Drive in a low gear, at a slow pace. Creating an impressive bow wave is a very good way to drown your engine but keeping the engine revving will prevent water’s entering the exhaust and causing a stall.

Should the engine come to a dead halt, it’s likely the worst has happened. Depress the clutch immediately and do not attempt to restart the engine. Damage may already have occurred; turning the engine will make it worse.

Should another vehicle be approaching from the opposite direction, make every effort to let it negotiate the floodwater first. This is for two reasons. One, if you both have to move across to let one another pass, you’ll both be in deeper water. Two, if the oncoming vehicle ingests water and dies mid-flood, you’ll be prompted to not try negotiating the flood yourself.

Finally, remember that brake pads can ‘aquaplane’ on wet discs, leaving you without brakes. On leaving the flooded area, apply the brake pedal for a short while, to dry the discs.

Merityre are a leading UK independent supplier of car tyres. Why not visit their website at www.merityre.co.uk and see where you can buy your next set of tyres.

Pre-Loved Pointers: Used Car Buying Tips

‘Caveat emptor’ is Latin. It means ‘Let the buyer beware’ and it makes the perfect maxim for anyone intending to buy a secondhand car. The rules for a successful purchase are simple enough and making a matchless deal is easy if you use these pointers.

1: Check the tyres. Car tyres save your life on a daily basis, simply by doing their job. Tyres with 3 millimetres or less of tread need replacing. Tyres can also be excellent tell tales. If they’re worn unevenly, the car’s suspension, steering or brakes could be at fault. Cracked tyres are generally pensionable and lumps or bulges in tyre carcasses suggest internal damage. Remember to check the spare tyre and bear in mind that tyre failure can be a killer.

2: Check the VIN. The car’s Vehicle Identification Number should match that in the logbook. If it doesn’t or is absent, the car could have been stolen, ‘rung’ or be two half cars welded together.

3: Check the history. This advice counts in two ways. Dealers must offer an HPI check by law. If buying privately, have one carried out yourself. An HPI check is to validate the car’s history and would reveal previous damage, theft, insurance claims, writings off and more.

Service history is equally important. If a main dealer or an approved concern has carried out servicing, the car’s automatically a better prospect.

4: Check the deal. Often, dealers can offer a warranty. The car may have some remaining manufacturer’s warranty and there may be ’sweeteners’, such as included accessories. Be very careful if buying from a private seller. Once the car is yours, you have very little comeback if it proves to be a bad buy.

5: Check the car. Unless professionally executed, accident repairs are easy to spot. Look for poor panel gaps, paint colour and texture mismatches, non-factory additions (e.g. lights) and damaged exterior trim. Take particular note of the car’s extremities: the nose and all four corners. Suspiciously thick, new-looking underseal can hide a lot, as can the boot carpet.

Look under the bonnet, for a clean engine bay with no rust or coolant stains. Dip the oil, which shouldn’t be like black treacle, and look underneath the car for spots of leaked fluid.

6: Check the mileage. The car’s MOT certificates should show a believable progression of mileage figures and the speedometer’s mileage reading should tally. Modern electronic mileometers can be easily tampered with so checking that the speedo screws aren’t butchered doesn’t always reveal a clocked car. That said, plastics and modern trim can wear. If the steering wheel rim and the pedal rubbers are shinier than the bodywork, chances are the car has an intergalactic mileage in reality. A worn, bursting drivers seat, is a dead giveaway, as are badly worn driver’s door mechanisms. Don’t forget that these parts could have been replaced, so if they look too new, be wary.

7: Check the performance. Have a realistically long test drive, using the vehicle as you expect to on a daily basis. Try the brakes, steering, transmission and electrical items. Should something be not as expected, be careful to not fall for the old ‘They all do that’ routine!

8: Remember these three golden rules. Unless the car you’re examining is so rare that there simply isn’t another, you can always find a rival example. Rule two: it’s a buyer’s market at the moment and you can always walk away. Rule three is simpler still: buy with your head, never your heart!

Merityre are a leading UK independent supplier of car tyres. Why not visit their website at www.merityre.co.uk and see where you can buy your next set of tyres.