So what's going on, and how can you protect yourself?
The show also claimed that the mechanics did not carry out the full checks on seven of the cars. They failed to spot under-inflated tyres, and in one instance they missed a nail in a tyre.
Reporter Rebecca Wilcox said: "I was shocked by what we uncovered and disappointed that we found such a large well known company on occasions exaggerating the urgency and quoting for unnecessary work and not carrying out all the checks they promised and as a car owner and car lover this story was very close to my heart."
She added: "Working with our expert John was definitely an eye opener I wish I could have him with me whenever I need to put my car in the garage. I consider myself to be a minor petrol head and was very surprised by how easy it can be to be misled"
ResponseKwik Fit has disagreed with the allegations, it said in a statement: "From the limited information the BBC has provided in advance of its broadcast we, and an independent expert, seriously disagree with most of its findings." It also said that as a result of its response to the BBC, the programme has: "accepted that a number of its conclusions were wrong".
It added that: "We stand by the majority of the recommendations we gave, and completely reject the way the BBC has calculated the cost of work it has deemed 'unnecessary' by not considering how worn these parts were."
And it has offered to have one of the cars independently tested to assess the quality of the recommendations.
However, it admitted that: "In a few cases we fully accept that our staff could have been clearer with their communication; for this we apologise and are intent on improving how we communicate our advice to customers."
It said that recommendations for replacement parts reflect manufacturers' recommendations and advice and information from the Royal Society for the Prevention of Accidents, saying: "The wear of items such as tyres and brake pads is not an exact science, but we believe ours is a professional and responsible approach which focuses first and foremost on the safety of our four and a half million customers."
And it added: "We have zero tolerance of staff recommending unnecessary work and any proven cases result in disciplinary action. We have a whistleblower line on which staff can anonymously report any aspect of malpractice from their colleagues and a senior management team will investigate and act on any reports."
It also emphasised that the company has a customer satisfaction level of 98%.
The BBC spokesperson said: "We stand by the programme."