ARGUMENTS over speeding are the top cause of bickering between couples in the car, according to a new study of what goes on when you're behind the wheel.
And older people are three times more likely to criticise their partner's driving than younger passengers, says online retail company BuyaCar.co.uk.
With the longest school holiday just around the corner it seems the findings of the survey of nearly 1,200 motorists spell a summer of trouble ahead for many couples.
BuyaCar asked customers ‘does your partner criticise your driving?'. The responses reveal that while less than one in ten people under 34 report their partner indulging in back-seat driving, more than a third of drivers over 55 criticise their partner's handling of the car.
Topping the list of complaints is speeding - but braking too late and too hard or taking unnecessary risks come close behind.
Other frequent causes of irritation for passengers are driving too cautiously or slowly, poor lane discipline and failing to keep a safe distance from the vehicle in front.
But the true extent of the frictions between couples on car journeys are best revealed in the comments of those who were inspired to offer additional thoughts on being driven by their partner.
The 10 favourite responses to the question: ‘What other reasons do you and your partner criticise each other's driving for?'.
1. "Criticising other drivers with a running commentary when I am trained in police driving tactics!"
2. "Being male"
3. "Giving way to buses"
4. "Thinking they know better than the Highway Code and Road Traffic Orders"
5. "Watching young ladies passing by!"
6. "Refusing to stop for a break"
7. "Taking too much time to park correctly in a space"
8. "Cutting corners onto the pavement"
9. "Shouting at other drivers"
Austin Collins, BuyaCar.co.uk managing director, said: "Based on our sample of nearly 1,200 drivers it seems we are a nation of nervous and critical motorists and passengers.
"It also seems that we become grumpier with our partner's driving the older we get, with less than one in ten motorists under 34 reporting disagreements over driving style but more than one in three among those aged 55 or over.
"From the comments we received it's fair to say that every kind of driving style, from fast and aggressive to thoughtful and careful comes in for criticism from the passenger, so taking a car journey together looks like a no-win for a lot of couples."
"Now we're heading toward the school holidays it looks like a summer of strife ahead on the roads of Britain, even before traffic jams or road closures come into the equation."