All wheel drive and tires

[BEJinFbk]

And I can only wish I had an Audi to experiment with... Nice Cars!

[misha]

I prefer Volvos.
Other makes comes and goes,but Volvo stays.

[MilehighV70XC]

Misha-- I was not aware a '97 850 came with AWD. I would imagine it is the same setup since I think it was Volvo's first attempt at an AWD. I don't think the states got that model, maybe only outside the state or select countries. Somebody please correct me if I am wrong.

BEJinFbk explained it pretty well. It has nothing to do with the transmission, hence why fwd cars don't have this problem. It is a 100% the viscous coupler

All those disc act just like a transmission clutch disc. When the front or rear start to slip the fluid heats up and starts locking the disc together. That why different tire diameters is catastrophic to the VC. When there is constant slip, like different diameters tires, there is a tremendous amount of heat that builds up and ruins the fluid and disc. Just like if you slip a clutch to much and it starts to smoke, Same concept.

Again, it is not the tire tread being worn that cause the problem. It is the different DIAMETER. Tread type might make a difference if you have let's say a very aggressive snow tire and a bald summer tire. I am just guessing on that aspect. Like I mentioned in my first post. You could have a 225/60/16 brand new and barely worn 225/55/17, as long as the diameter is the same everything should work just fine.

BEJinFbk-- I have always been a Volvo and Audi guy. I definitely prefer to work on a Volvo over an Audi. Since they are over engineered you pay for it. Way more technical and no space to work without removing a lot of stuff. The price for parts is ridiculous compared to a Volvo. With that said, you forget about it the second you get behind the wheel, The Audi is definitely a drivers car. You can really feel the 15k-20k price difference when brand new. Audi is just more refined.

[misha]

Yep....850 introduced AWD in November 1996.
U.S didn't had them.They were EU & Canada models.
https://en.m.wikipedia.org/wiki/Volvo_850

[BEJinFbk]

I had a major car crush when the first Quattro's showed up.
I thought "What an Awesome Fairbanks car!" And sure enough, the
Audi's that I've been fortunate enough to drive have never disappointed.

But somehow, I got sucked into the Volvoverse and here I am!
LOVE the seats...

[tom4342]

I am a big fan of Volvo's now since owning this 98v70 now for 5 years