My curiosity was raised very high after Tom's recent "disaster". I called my friendly Volvo parts guy and asked if he could research when the 960 piston ring design changed when he had some time. He called me back about a half day later to tell me that the part number changed at engine #396,322. My engine number is 532,021 so it seems to be the later design. My car is also a '96 model. His documents had no cross reference between engines and VINs or years. Anyone have a number before 396,322? What year is the car?

On another note, I think it is reasonable for Volvo to only service rings with new pistons. In my 30 odd years of being around engines, it is rare to have a ring fail without a damaged piston as well. If the ring grove isn't right, a new ring will not last because it won't have the proper clearances and support. In checking some of the clearance numbers in the book, I'm amazed at how tight this design is. (No room for error or mistreatment!)

I'm guessing, perhaps hoping is a better word, that the major reason for Tom's disaster was overheating. So.... if the low coolant light ever comes on in your 960 STOP immeadiately to avoid a disaster. Comments?
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'96 965 at 89K. Had '85 745 Turbo Diesel for 200K.