Are broken coil springs a known issue on Mercedes-Benz?

My car is a 2005 Mercedes-Benz SLK 350 7G-Tronic automatic. It has covered 68,000 miles and has been well looked after and serviced regularly. I've had it two years and, after about three months, I found my front offside coil spring broken and replaced it. I have since replaced all the shockers, front and rear. It went in for a service yesterday and it was found that the rear offside coil spring had broken, so I had that replaced. Now I am riding on 225/40 R18 92W XL on the front and 245/35Z R18 92Y XL on the rear. Why am I having spring breakage problems? Is it a fault with the car or am I just unlucky?
They are quite common on Mercedes-Benz. But the problem will be compounded by the ridiculous wheels and tyres. These cars are far better on more sensible 17-inch wheels with deeper profile tyres all round.
Answered by Honest John on

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