The last two times I went to the mechanic workshop, I saw two cars: both peugeot 406 to be specific and i was told that the timing belt cut off while they were driving.

The second time I went, i saw another peugeot 406 and it was the same timing belt problem.
And to fix the problem, the mechanic have had to dismantle the engine and reset the valves, which took them about three to four hours plus some work on the engine.

So the question is how often should one change timing belt to avoid this problem.

adeblow:
The last two times I went to the mechanic workshop, I saw two cars: both peugeot 406 to be specific and i was told that the timing belt cut off while they were driving.

The second time I went, i saw another peugeot 406 and it was the same timing belt problem.
And to fix the problem, the mechanic have had to dismantle the engine and reset the valves, which took them about three to four hours plus some work on the engine.

So the question is how often should one change timing belt to avoid this problem.

Depending on your car make and model. Different car manufacturers have recommended mileage for timing belt replacement. For instance, Toyota Sienna 2004/2005 on the 3mz fe engine recommends timing belt replacement at 90,000 miles. But again, you may not go wrong with what @Gazzuzz has recommended provided you purchase a genuine one.

thanks guys very informative