V70 XC or AWD - problems?

If you drive the car on mismatched tires that have minutely different diameters, damage can be done to the viscous drive. You may want to ask the original owner if they ever replaced the tires, and if so, how many did they replace? The correct answer is all of them and at the same time. As long as it is properly maintained, tires and all, it should be fine.

Hmmm, that's a good question. Short of opening up the system, or hearing and feeling a prob, I'm not so sure you can tell that. Any chance any of them are still under warranty. That's about the best assurance you can hope for. BTW, these systems are generally accepted as being quite reliable. The situations I mentioned above can damage them over time, but you should be okay if the dealer has looked it over.... the warranty helps cover that though.