Motorists are being advised not to fall foul of a new type of vehicle clocking scam, which experts say ‘could prove to be deadly’.
Cheap ‘mileage blocker’ or ‘mileage freezer’ devices sold online are able to lower and even pause the mileage of a vehicle when it is being driven to suggest it has been used far less than it truly has.
UK sellers of these products are taking advantage of legal loopholes around clocking devices by caveating that they are ‘for off-road or research use only’.
However, they are also advertised as ‘totally untraceable’ and ’99 per cent undetectable’, raising serious concerns that fraudsters can use them to falsify a car’s mileage before selling for an unjustly inflated price.
Car clocking is making a dangerous comeback: Vehicle history check service HPI has warned that ‘mileage blockers’ that conceal a vehicle’s true amount of use but can legally be sold in the UK and could have ‘deadly’ consequences
In fact, a recent study shows that UK buyers overpay by around £5,000 when they unsuspectingly purchase a clocked car.
Use of these blockers also puts oblivious motorists at risk because a vehicle’s parts will often be substantially more worn than the faked mileage suggests they should be.
What are ‘mileage blockers?’
Mileage blockers and freezers are being advertised for sale around £200 to £250 online with specific attachments for individual car models.
They connect with smartphones to instruct a car’s electronic brain and odometer to reduce or stop entirely recording the true mileage while it is being driven.
Vehicle data experts HPI – which raised the issue to This is Money – say the practice is particularly unscrupulous because an owner can still provide a complete service record history with bogus mileage that looks genuine and legal.
A number of businesses across the UK are selling these products online, either supplying the devices with instructions or offering installations courtesy of ‘fully qualified technicians’.
Checking sites that appear on the first page of Google searches, three reviewed by This is Money do state that the devices are illegal for use on public roads.
However, this information isn’t provided up front and is often the last point in a ‘frequently asked questions’ section, usually lower down on their pages.
What is advertised up front, though, is that any use of these plug-in products is almost entirely untraceable.
One claims: ‘Real information is not stored in any memory or module, thus no diagnostic testers is able to trace the mileage that was stopped while using our Mileage Correction Tool’.
Another states online: ‘Our mileage blockers are 99 per cent undetectable although some ‘main dealers’ may be able to detect it if you have not set it to ‘deactivated’ mode. Diagnostic testers cannot detect the mileage has been frozen.’
Some also advertise the fact that the mileage blocker can be adjusted, meaning users can manipulate the mileage covered, for instance to show 50 per cent of actual miles covered or to stop any miles being added at all during the period it is used.
‘Testimonials’ from customers include an example from ‘John’ who is said to have used a mileage blocker when taking his BMW X5 on ‘track events’ to ‘stop the accumulation of track miles, which he felt didn’t represent the car’s standard usage’.
This is despite the fact driving hard on track will increase the wear and tear on consumable parts, especially the brakes, which is accelerates the impact of mileage on a vehicle’s mechanical condition.
Are mileage blockers illegal?
CarVertical estimates that clocking fraudulently adds 29 per cent to the price of a second-hand car in the UK today.
Based on an average used car price of £17,064 (based on AutoTrader’s December Price Index), buyers overpay by £4,949 when they unknowingly purchase a clocked vehicle.
Yet, under UK law, the act of altering the mileage on a car is not illegal.
However, it is illegal to sell that car without disclosing any known mileage discrepancies to the buyer.
It is also possible for vehicle traders to be prosecuted for mileage fraud under the Consumer Regulation Act, though only if a victim can prove that they have clocked a car for financial gain.
As you can already tell, calling the law around clocking a ‘grey area’ is an understatement.
The last time the Government seriously looked into the activity was in 2016.
This [oddly] was part of a consultation paper on road worthiness testing in tractors, which also raised concerns over clocking and the activities of mileage adjustment companies in general vehicles.
John Hayes, then minister of State for Transport, said the responses to the consultation would help make changes to legislation.
‘We are aware of some recent concerns in the media that the manipulation itself is not illegal, only the subsequent sale of the vehicle,’ he said.
‘We are keen to understand respondents’ views on this matter.’
However, in September that year, the Department for Transport issued a non-committal response to the car clocking issue, simply stating: ‘The Government will consider further what measures, if any, are needed.’
The response drew criticism from various consumer rights groups, car-trade businesses and the Chartered Trading Standards Institute for failing to seriously address the issue at the time.
And it is clear from the latest online activity around mileage blockers that businesses continue to take advantage of the loopholes today.
This is Money asked the DfT about its future plans to tackle vehicle clocking, though received the following lacklustre response.
A spokesperson said: ‘When buying second-hand cars, consumers can check the MOT history – including mileages recorded at the annual tests – on gov.uk.’
They added that ‘enforcement is a matter for the police and courts’ and any company suspected of providing fraudulent services can be reported here.
Jon Clay, identification director at HPI, said: ‘Mileage fraud and odometer tampering remains a grey area as far as the law is concerned.
‘The difficulty is that in the eyes of the law, to sell a vehicle with an incorrect mileage and actively encourage it, as is being done with mileage blocker devices, isn’t a crime.
‘It’s the non-declaration that it is incorrect where the offence has been committed, which can be very difficult to prove.’
Jon adds: ‘Potentially, a reputable dealer could be liable for selling a car with false mileage after being unwittingly duped by a scammer, but there is seemingly no direct route to prosecution against the person who altered the mileage in the first place, with a device such as a mileage blocker.’
This is Money has contacted UK businesses that sell mileage blockers. Here’s what they had to say…
What UK sellers of mileage blockers have to say
This is Money contacted three UK business it found to be selling mileage blockers online.
While one failed to respond to our request, two issued comments on the sale of these products, both with ‘we load the bullets but don’t pull the trigger’ statements.
CarCode, based in Mildenhall, Bury St Edmunds, told us: ‘As the supplier of mileage blocker devices, we would like to clarify that the way our customers use these devices is completely out of our control.
‘While we acknowledge that use of a mileage blocker can be controversial, we also want to emphasize that there are several legal and fair applications for the device we sell.
‘Our product is designed to provide high quality and reliable solutions to the general public. It is important to note that the responsibility lies with the individual to use the device in accordance with the law and ethical considerations.
‘We do not condone or support any illegal activities. We encourage our customers to use our products responsibly and within the boundaries of the law.’
TorxTuning in Leighton Buzzard, Bedfordshire, explained: ‘Our mileage blockers are supplied and fitted for testing purposes only, and we want to emphasize that we do not condone the illegal use of these devices to deceive potential buyers.
‘The mention of being ’99 per cent undetectable’ is aimed at highlighting the technology’s effectiveness for legitimate purposes, such as testing and diagnostics.
‘It’s crucial to note that the device is designed to freeze the mileage for testing purposes/diagnostics. Or if a new instrument cluster with higher mileage, than the cars actual mileage is fitted, this device will freeze the mileage from going up until the correct mileage has been reached.
‘This is a very common solution for people who retro fit virtual instrument clusters into their vehicles as it is extremely difficult to alter the mileage displayed, so you must use a blocker to regain the correct lawful mileage. We strongly discourage any illegal activities associated with tampering or falsifying mileage for deceptive purposes.
‘We are committed to promoting ethical practices within the automotive industry and encourage users to adhere to legal and transparent dealings when using our products.
‘Anyone who uses this device to carry out any illegal or unlawful activities Is acting on their own accord and is not the responsibility of Torxtuning.’
Any act of concealing a vehicle’s true use can have dangerous consequences if owners are unaware that components are more worn than the falsified mileage suggests
Clocked cars: the hidden risks
Jon Clay from HPI says that while a vehicle’s mileage is intrinsically linked to its value, the false readings given as a result of use of blocking devices often correlate to mechanical issues and faults later down the line.
While this can lead to hefty repair bills, concealing a car’s true mileage is also incredibly dangerous and can potentially be deadly.
‘All the safety features and modules in a modern car, such as airbags, ABS and ignition, feed information into the vehicle’s central computer system,’ he said.
‘Each time an issue arises, such as a fault warning, – a ‘snapshot’ of the vehicle’s mileage will be logged.
‘Unless a vehicle’s mileage is wound back by a clocker who knows to alter the mileage readings on all modules as well as the odometer, these will be out of sync.
‘This will lead to issues with safety warnings – making it potentially very dangerous for the driver, passenger and other road users.’
We need tighter rules around clocking devices, experts say
Motoring experts, road safety groups and trading standards officers are all in agreement that laws around clocking devices need urgent attention.
Jack Cousens, head of roads policy for the AA, said: ‘Clocking cars is a tried and tested illegal scam which puts older, more dangerous cars in the hands of unsuspecting drivers.
‘Despite websites stating that mileage blockers should only be used for ‘research and vehicle testing’ purposes, the fact that they boast about their lack of detection highlights the real reason someone may buy in the product.
‘We’d like to see tighter rules around the sale of these devices alongside car key cloning units, so that only those with a legitimate need to purchase them can do so.’
RAC spokesman Rod Dennis said the fact mileage blockers are being sold so ‘shamelessly’ is a ‘real cause of concern’.
He told us: ‘The advertised price of a used car is often determined by its age and mileage – while there’s no way to disguise the former, the fact it appears to be so easy to turn odometer readings back and make a heavily used car look as though it’s been driven a lot less can’t be right.
‘Drivers could unwittingly end up paying well over the odds for cars that have been driven far more than the fake mileage suggests.
‘There’s also a very good chance they’ll have a nasty surprise after buying the car due to problems associated with the number of miles a vehicle’s actually been driven.
‘We’d encourage Trading Standards and police forces to crack down on these unscrupulous outfits – fake mileages on cars are in nobody’s interests apart from those individuals trying to sell cars for far more than they’re actually worth.’
Owen Kennedy, a senior Trading Standards officer at City of Doncaster Council, told us: ‘These devices can cause other problems than simply changing the value of a car.
‘Service and maintenance schedules are all based around the age and mileage of the vehicle, and so a vehicle that has had the mileage reduced in any way may not have undergone crucial checks and replacements. So, there can be safety concerns raised as well.’
Mr Kennedy added: ‘With regard to mileage blockers and adjustment services, there are few legitimate uses for these, and so they could be controlled.’
IAM RoadSmart director of policy and standards Nicholas Lyes, told This is Money: ‘The legal and moral issues aside, a vehicle with more wear and tear than the mileage indicates could be a death trap on wheels.
‘In 2022 alone, there were almost 500 serious or fatal collisions because of a defective vehicle with brake and tyre faults the biggest culprits.
‘In 2016, the Government said it would consider making changes to the law on vehicle clocking, but we are yet to see anything substantial that’s been brought forward.’
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