Any car with 100-150k on it is most likely going to need some work unless it has been very well maintained. Having owned 2 850's, here is my take on them.

The only 850 engine mounts that ever go are the upper torque (a cheap DIY) and the lower crank. The tranny and other two engine mounts are hydraulic and are bulletproof. Good thing too because they look like they are a bear to replace..:) The upper torque is the only mount that might go before 150k.

The evaporator failure can be prevented by changing the cabin air filter and cleaning that area above the evap to prevent debris from getting to the evap. The evaps rusts out from debris.

Unlike the RWD cars, the suspension bushings pretty much last forever. The only bushings I've needed to replace on my 20 year old 850 are the rear shock mounts. All the others are original and fine..

One CV joint replaced in 255k. No maintenance needed. If the boot tears, just replace the joint when it gets noisy. I still have the original on the driver's side.

240's are great, but 850's (and early V70/S70's) are very well built FWD cars that will last a long time too.

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Current - 95 855 GLT Sportwagon 255k, Formerly - 90 244 DL 300k