my 1998 v70 wagon's engine was destroyed--at 60 mph on a highway--by a failed timing belt caused by a failed tensioner. the car had 126K on it. i learned from my volvo shop that i was one of the unlucky 1998 owners that had a 1999 electronic tensioner, instead of a '98 mechanical one, which therefore should have been replaced either at 70K or 105K, depending on whom i spoke to. (the '98 mechanical part would not need replacing, they tell me, until 140k.) i had regularly serviced the car every 5k. since i had no knowledge that my '98 car had an original '99 part in it, the fault lies either with volvo or my volvo dealer. has anyone else had such a problem or heard of one?

 

You must mean you had a Mechanical tensioner and not the Hydrolic tensioner.
Yes I have seen this many times before.
Thats why I always stress to have all pullies replaced when doing the belt.

E ven if you had the hydrolic tensioner the pulley for it should have been replaced.

Have you ever had the timing belt replaced?