Some garages are charging car service labour rates as high as £170 an hour, a study revealed yesterday.

The highest hourly rates are in London, with £100 an hour being reached in 80 per cent of British regions surveyed by the Warranty Direct company.

Labour rates ranged from an average £116.53 an hour at London franchised dealers to just £32.12 at independent workshops in Lanarkshire, Scotland.

The highest hourly rate found was £170.61 in London and even in Lanarkshire the highest rate found was £112.80.

The five most expensive regions for franchised dealers were London, Middlesex, Hertfordshire, Surrey and Warwickshire.

The disparity between franchised and dealer labour rates was starkest in the West Midlands, where the average was £66.35 an hour, but was as high as £117.45 at franchised garages, and as low as just £23.50 at independent workshops.

In all, the survey covered more than 3,000 garages.

Warranty Direct spokesman Duncan McClure Fisher said: "After a couple of years of excessive rises, mechanic labour rates have started to stabilise but it's obvious that there is still a major gulf between regions, and independent and franchised garages."

He went on: "The latest findings show that garage rates are still extortionate, but motorists can help themselves by asking how much they charge an hour. Unfortunately, once you get the bill, it's too late to yell."