Guys,

Thanks for good feedback. A few additional comments:

1. I keep temp wheel at 75, but temp here in Atlanta has been in high 80s, low 90s lately, so my problem does not appear to be same as GMERCOLEZA'S.

2. Interestingly enough, when the car had head gasket done, my mechanic left me with an unsolicited quote for a "Drive Belt Tensioner Shock/Strut"
This was done in the last two weeks. (I wanted to try head gasket replacement myself, but engine started leaking, smelling of burnt oil pretty badly in past month, and since my son and I are driving up to Indy tomorrow to see McLaren-Mercedes win F1 race, decided to take car to mechanic.)

Does his recommedation to replace the "Drive Belt Tensioner Shock/Strut" sound like it would cure slipping belt/tensioner problems?