Tyres most likely to cause MOT fails


  • New research finds tyres most likely to cause MOT fails and dangerous defects
  • Dangerous defects on tyres were found in 5.5% of tests
  • Brakes, lamps, reflectors and electrical equipment cause the most amount of ‘standard’ defects
  • Experts provide advice to owners on how they can avoid common pitfalls

New research from leading motorhome rental company, Camptoo has detailed the main reasons why Class 4 vehicles fail their MOT’s, finding tyres to be the category with the largest number of dangerous defects. 

If found during a test, it means the vehicle owner cannot drive away from the test until the issue is fixed, often resulting in the owners being left with costly repairs.  According to data from the DVLA, dangerous defects on tyres were found in 5.5% of tests during 2019-2020 – 77% more than brakes, which was the next highest at 3.1%. Brakes, lamps, reflectors and electrical equipment was the category responsible for the highest percentage of defects, more specifically lamps and signalling causing the most problems within this category, however, figures are showing a slight decrease over time. 

The study found that in the 2019-20 financial year, just over 30% of Class 4 vehicles failed their MOT on the first time of asking. This figure was shown to gradually decrease over the last few years from 40% since 2013-14 however, it is still high and there are measures Class 4 vehicle owners can take to ensure they pass, saving them money on often costly repairs. 

With this in mind, we asked a few experts if they could provide any tips for owners on vehicle maintenance. 

Philip Westfall, director of marketing at RV Ezy told Camptoo there are a few things every owner should be doing before

He said: “Even if you’re not a campervan expert, there are still some checks you can carry out yourself before heading to the MOT to increase the chances of your vehicle passing the first time, and this starts with a test drive. 

“Take your van for a varied drive (motorways and country lanes) and listen or for any unusual noises or any handling problems that are easy to miss when you’re excited to get to your pitch and get the BBQ out! There are some simple checks to carry out in addition to your test drive, including tyre pressure, tread depth and topping up all the fluids, especially the wipers that we always forget about during summer months! If you have the time, I always recommend testing your vehicle’s lights in the evenings, either by parking it on the driveway and walking around or simply pointing it at the garage wall. It’s also worth shopping around for the best price. The typical cost of an MOT for a Class 4 vehicle is £54.85, however, many local test centres may offer a discounted rate.”

With the research findings showing tyres caused the highest percentage of dangerous defects, we asked Mike Skoropad, CEO of United Tyres if he had any advice.

MOTs require Class 4 vehicles to have at least 1.6mm of tyre tread, and for tyre tread to be even,” he told Camptoo.

“The easiest way to check whether your tyre has sufficient tread depth is to use the ‘20p test’ –  simply put a 20p coin in the tread of the tyre and look directly across the coin. The top of the queen’s head should not be visible in the tread. If you can see any of the outer band around the coin, then your tyre tread is definitely under 1.6mm and your vehicle will fail its MOT on these grounds. As far as the evenness of tread goes, the best way to diagnose this is to run your fingertips on the tread of the tire. The tread should ‘feel’ even to the touch. Pay particular attention to any differences in wear between the outer edges of the tyre tread and the middle of the tread. If the tyre is more worn on the outer edges of the tyre then this indicates that the tyre has been driven on underinflated for a long time.”

Camptoo’s Head of Wanderlust Ed Bassett also commented on the research, saying; “Nobody likes taking their vehicle in for an MOT test, but it is vital in making sure motorhomes and campervans are fit to be driven on the road. Although the number of first time failures is decreasing, 30% is still a large amount and that’s why we decided to look at exactly what was causing these problems. Hopefully, the tips and tricks provided by our experts will help even those owners with very little mechanical knowledge pass first time and avoid the costly repairs or hassle of not being able to drive their vehicle away from the test site.

Additionally, we would recommend an annual service and a habitation check on vehicles as a matter, of course paying attention to your gas safety certificate. You can contact the Approved Workshop scheme for nationwide assistance on servicing” 




Notes to Editors: Camptoo’s Head of Wanderlust Ed Bassett is available for comment or interview on request.

For further information or analysis, please contact jonathan.routledge@blueclaw.co.uk