I just bought a 91 350SD (same engine) with 200K miles, original engine, never touched. I belive it still runs great, the the owner says it does not consume any oil.

Some came out of the factory good, and some bad. The bad apples blew up before 100K miles. If after about 120K miles, and the engine is still good, you know you have a good engine.

If the service records are there, and the car runs good, I say go for it. This is one case were high mileage is actually good, the engine has proven itself. I wouldn't touch this car with a ten foot pole if it had 75K miles.

These W140 cars are not cheap to operate, compared to a W126. Make sure the air conditioning and climate control is working, and paroozle thru the maintenence records to see if the evaportator has ever been done, its a 26-hour job with an expensive part, big $$$$. Things like automatic door and trunk closers and a complex vacuum system drive the maint. prices up.

Let us know how you do.