Car manufacturers offering longer warranties could be leaving motorists short-changed, according to research.

The study, conducted by Warranty Direct, examined the latest warranty documents from manufacturers advertising warranties of four years or more.

Mitsubishi, Renault, Subaru, Hyundai and Kia now offer warranties ranging from four to seven years from the initial purchase date, but a closer examination of the small print reveals major discrepancies between the advertised cover and the time elapsed.

Last year, Vauxhall revealed that its new cars would no longer be offered with its ‘Lifetime’ warranty, instead reverting to the industry norm of three years or 60,000 miles. 

This has raised questions over the value of longer warranties, with many manufacturers enforcing mileage restrictions and excluding complex components and failures classified under ‘wear and tear’. 

Mitsubishi has recently announced that it too will offer a five-year warranty, but all models will be subject to a strict mileage cap of 62,500 (except for the L200 which is covered for five years or 125,000 miles). 

Similarly Renault, Subaru, Hyundai and Kia all eventually cap mileage at 100,000, but Renault drivers may be unaware that their warranty will expire if they reach this between 25 and 48 months of ownership.

Kia is slightly more generous with a 100,000 mile limit after 36 months. Kia’s ‘wear and tear’ policy also outlines restrictions based on mileage. This vague clause could leave Kia owners vulnerable to judgment that their mileage is too high for the component to be covered.

Renault and Mitsubishi also stipulate that ‘normal’ wear and tear will not be covered. Most parts eventually fail due to wear and the definition of ‘normal’, ‘gradual’ or ‘premature’ appears open to interpretation, with the owner frequently exposed to significant bills.

In Subaru’s five-year warranty only the powertrain is covered after year three; this is defined as the engine, transmission and driveline. Any complex electrical faults will be the responsibility of the customer after the standard three years or 60,000 miles.  Also, Subaru’s five-year warranty doesn’t apply to the WRX STi model, which only has a three-year manufacturer warranty.

Statistics from Warranty Direct’s Reliability Index show that on average 15% of Subaru Legacy models will require attention for electrical faults and overall repair bills have escalated up to £2,304.30, suggesting that buyers could be faced with large bills beyond the standard warranty cover period.

Higher mileage Hyundai drivers will also need to prepare to fork out for items not included in the ‘unlimited’ mileage offer; wheel bearings, all ball joints, bushes and dampers are covered for a maximum of five years or 60,000 miles.

On closer inspection, Kia’s headlining seven-year warranty also excludes the air conditioning after two years and the audio and navigation systems after three years or 60,000 miles. Given that some Kias are prone to faults with more complex components (notably the 55% of Picantos on record have suffered electrical failures) this could be a cause for concern.

All of these policies stipulate that the car must be serviced by an authorised retailer and, for its electric vehicles, Renault will only honour the warranty cover if the owner’s charging point meets a required standard. 

Managing director at Warranty Direct David Gerrans said: “Prospective car purchasers need to be wary of the limitations of policies that may promise total peace of mind beyond the usual three years or 60,000 miles as they may not be all that they seem.

“Mitsubishi’s recently introduced five-year policy is a prime example of an extended warranty policy which is heavily restricted in favour of the manufacturer. “Such offerings should not eclipse all other factors when selecting a new car. Motorists who cover high mileages or plan to replace their car after a short time are very unlikely to reap the full benefit of an extended warranty, so should take other considerations into account when making the purchase.

“In all instances, buyers should protect their interests by maintaining their cars in line with manufacturer guidelines, a common stipulation that could wipe out your warranty cover if ignored.”