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NEWSwww.ntda.co.uk SERVICE BULLETIN

4-2-2? No Thanks!

No, 4-2-2 is not the latest formation employed by Fabio Capello to get the best out of his England team; rather it refers to suggested changes to the MOT test in the UK to bring us more in line with the rest of Europe. At the moment, EU law says that vehicles should undergo their first test when they are four years old, with a subsequent test every other year thereafter. This is familiarly referred to as 4-2-2, as opposed to the UK requirement for a test after three years and annually thereafter (3-1-1).

While drivers might welcome the idea of not having to pay for an MOT test so often, many in the vehicle servicing and fast-fit sectors, including the NTDA, believe that adopting the European norm of 4-2-2 would be a retrograde step and one that could have potentially serious consequences. As Director Richard Edy put it in a recent magazine article: “Any scheme that extends the time period between testing will inevitably lead to an increase in the number of unsafe vehicles on our roads and in more accidents.”

Far from embracing the European model, Edy believes that other European states would do better to fall in line with the UK, as this would reduce accident levels. He said: “When it comes to road safety, adopting the lowest common denominator is a backward step and, if anything, the MOT test should be tightened up, not relaxed.”

With the recent raft of legislation coming from Europe

regarding tyre noise levels and the introduction of tyre labelling, detailing wet grip performance, fuel efficiency and noise rating, it seems strange indeed that a step which could fundamentally affect road safety is even being considered and it has been said that the legislators would have been better employed looking at safety issues.

Another 12 months of neglect

But back to the proposed 4-2-2 MOT test. The reason for prolonging the testing period is that modern vehicles are much more reliable and it is true that intervals between services have steadily lengthened. However, tyres are subject to constant wear, day in, day out and the fear is that, by extending the MOT period, motorists will have another 12 months in which they will forget to examine their tyres.

Yes, motorists are supposed to check and maintain their vehicles between tests, but experience shows that, when it comes to tyres, few do so. Modern tyres are extremely forgiving products and the fact that surveys continually show that the majority of drivers rarely check tyre pressures or examine tyres for cuts or tread depth illustrates the high quality of today’s tyres as they continue to perform, despite the neglect.

It is a sad fact, but if a car passes the MOT test, then many drivers act as though their tyres are legal for another year. A car can pass the MOT with just over the legal minimum tread depth of 1.6mm remaining

Always replace TPMS sensor nut, seal and washer (items 1, 3 and 4 in the diagram below) when the sensor is removed from the wheel rim.

l After changing tyres or tyre valves, the TPMS valve must be registered to the TPMS unit. This procedure is set out in the owner’s handbook, which should be with the vehicle, or which can be obtained from any Mazda dealer.

l Care must be taken when inflating or adjusting the tyre pressures. Do not apply excess force to the valve stem as this could cause damage to the valve stem.

Should you require further clarification or assistance, then this can be obtained from any Mazda dealer. Dealer locations can be obtained from the Mazda website www.mazda.co.uk

MOT under the spotlight...

Mazda Advice On TPMSMazda Motors has written to the NTDA to advise that the company is now fitting tyre pressure monitoring systems (TPMS) to some of its vehicles.

In the UK, the models affected are Mazda6 Sport and SL (produced after 5th September 2007) and the Mazda3 MPS (produced after 12th May 2009).

The letter says that NTDA members should be aware of the following procedure for Mazda vehicles equipped with TPMS.

l DO NOT use metal stem caps – fitment of metal caps could cause corrosion of the valve stem, causing the valve to break. This breakage is caused by two dissimilar metals reacting with each other.

l If TPMS valve is replaced or removed, ensure that the sensor fixing nut (indicated on the diagram by an arrow) is tightened to a torque of 8 Nm. Excessive tightening of this nut can cause the nut to fail, with resultant loss of the tyre’s pressure.

Note: The initial installation torque of the TPMS sensor fixing nut is 8 Nm. After applying air pressure to the tyre the torque decreases to 2-3 Nm. Do NOT retighten the TPMS fixing nut after charging the tyre with air pressure.

Installation torque of the valve core is 0.2 -0.4 Nm.

We are grateful to Mazda for their help in compiling this Bulletin.

NEWS www.ntda.co.ukSERVICE BULLETIN

on its tyres and the thought that a motorist could then drive around for two years before being tested again is frightening.

At the moment, according to the Tyre Industry Federation, 12% of tyres are illegal on replacement and, in difficult economic times, this figure will inevitably increase.

Opposition to the 4-2-2 comes from many quarters, with RoadSafe warning of more crashes, caused by poorly maintained vehicles. The organisation points out that UK testers already identify 8.5 million cars with defects every year and extending the test period would only exacerbate the situation.

The Independent Automotive Aftermarket Federation (IAAF) has also questioned the proposed changes and points out that, in a review carried out by the Department for Transport (DfT) in 2008, it was concluded that a significant number of additional road traffic accidents and deaths (estimated at 400 extra deaths and 2,500 serious injuries a year) would result from reducing MOT test frequency. Nothing has changed over the past two years, says the IAAF and adds that extended test periods would also mean increased pollution form poorly-maintained vehicles.

Call for tougher tests

Having rejected the call for extended periods between tests, many are suggesting that these tests should be made more stringent, and nowhere is this more evident than in the case of tyre testing. The MOT Trade Forum has come up with a number of recommendations concerning changes to the MOT test with respect to tyres. The current failure rate of MOT tests attributable to tyres is estimated at 11% and this would no doubt rise were the Forum’s suggestions to be adopted.

Before looking at the recommendations, it is worthwhile reminding ourselves of what is required vis-à-vis tyres in the current MOT test.

The following is taken from the website:UKMOT.com, under the heading “Tyres & Wheels” and summarises what the tester should look for...

Tyre condition

A failure with respect to tyre wear will result where:-

The grooves of the tread pattern are not at least 1.6mm throughout a continuous band comprising: l Central 3/4 of the breadth of tread l Entire outer circumference of the tyre.

Tyres must be correctly matched with regard to: l Typel Size l Structurel Location on the vehicle with respect to the axles.

Also examined:l General condition of tyrel Condition of valve

Tyres fail if they have serious cuts, bulges or other damage. The wear on the tyre is checked with a tyre tread depth gauge to ensure compliance. The tyres are examined to ensure that there is no fouling with any part of the vehicle.

Note: The condition of the spare tyre is not part of the MOT.

Wheel condition

Inspection to reveal:l Damagel Distortionl Cracksl Distorted bead rimsl How securely attached to the vehicle l No wheel-nuts or studs missing

An externally fitted spare wheel or spare wheel carrier must not be so insecure that it is likely to fall off.

I think that most would agree that this is hardly the most stringent of tests – certainly the MOT Trade Forum does and the following are its suggestions for toughening up the test. The first recommendation is that the inspection should be across the whole width of the tyre and not the arbitrary 75%, as is currently required.

Secondly, research has shown that braking distances (especially in the wet) are significantly reduced, the greater then tread depth. As such, it is proposed that, in the interests of road safety, the minimum tread depth for an MOT test should be increased from 1.6mm to 2mm. On this subject, it should be noted that many organisations, such as the police and Government vehicles, habitually change their tyres when the tread depth falls to 3mm.

The final point is that consideration should be given to introducing tyre age as a reason for failing the MOT

test. This raises a number of questions, not least of which is “how old is too old?”

A Coroner recently wrote to the DfT, drawing attention to a fatal accident which was found to be at least partly caused by the vehicle’s 13 year-old tyres and calling for a ban on tyres over 10 years old.

The NTDA drew attention to this subject back in 2008, when the Association joined forces with the RAC Foundation to mount a consumer campaign, urging motorists to check the age of their tyres (from the code on the sidewall) and their condition. Although there is no recommended “use by” date for tyres and much depends on maintenance levels and the conditions in which they are stored, many vehicle manufacturers recommend that tyres more than five years old should be replaced.

The final word on the whole tyres/MOT subject comes from Richard Edy when he says: “Tyres are a safety-critical component and the only things that keep a car in contact with the road. Their importance to road safety cannot be over-estimated and the MOT test should reflect this. Moving to 4-2-2 would send all the wrong signals to the motorist and, in terms of safety, would be a recipe for disaster.”

If there are any topics that you would like to see included in future service bulletins please contact the Editor Peter Gardner by email at:petergardner5@btinternet.com or NTDA direct at: info@ntda.co.uk or call 0889 67 07 07.

Issue 10/10