As a re-design of the 850,'98s had "some" problems when they were new, but they were (mostly) corrected under the recalls and original warranty.

Thereafter the same things break that have broken since the first 850s.'99-ups are "drive by wire" and there have been some complaints about THAT, and it's $$$ to fix and (of course) Volvo isn't standing behind the product. The AWDs have also been troublesome, do a search for "bevel gear" or "angle gear". Consumer Reports says "Avoid". Turbos aren't much more trouble, per se, since the engine block is stronger and the crankshaft is forged. Mine has 140k on it still uses no oil and still has the original turbo (and the original clutch).

-Punx