I acquired car with two sets of different tires - so this only is why I
ask. Thx for talking me out it. In fact I have never bought tires
outside of tirerack.com for all my cars and over 300k miles :-)

Tiger schrieb:

Poor guys, depends of course how they were crossing the safety edge.

For the normal driver even different brands at front and rear axes dont
do any harm als long as left and right tire on each axis is identical.
Width 195 front and 225 rear is physically as different as old and new
tires.

The ESP/ABS computer controls rpms of wheels and therefore should
account for different tire types or ages.

If you prefer absolutely safety, of course, sell your used tires at 60%
profile depth or after two years of use and buy four new ones. Makes
sense for comfort and even economically.