Your comment about "biodegradeable" wiring is the problem I am currently dealing with on my 1987 745. I let a mechanic convince me that I didn't need to replace the wiring harness [Error] and now it looks like that was the thing I've should have done first, a judgement reinforced by my experience on the 85 245. Between 120K miles and 170K miles the 1985 never ran right until the wiring harness was replaced and a little later the throttle body was cleaned. For that car, I also replaced the motor mounts circa 110K miles and not too many miles later, the rubber suspension parts in the rear end were replaced which made it ride and handle like a new Volvo. The steering rack gives up at 135K miles or so, but the life of your new one can be extended with a yearly flushing and cleaning. Any protective rubber parts should be replaced when they look like they are beginning to crack. If I want to keep my car on the road for the next ten years without having to deal too much with finding parts, I'll need a zero tolerance attitude toward the condition of these parts and replace them while they are still available. I will likely need to build up a parts inventory because I've noticed a ramping up of prices and increased incidences of unavailablity but in 10-15 years my Volvo will be a collectable and the lot of car plus parts will likely recover the costs of its final decade of ownership.