I managed 212,000 on a '93 Lexus SC400. Even though I didn't drive especially hard and used synthetic fluid in the differential, the differential failed at 160,000 and they put in a used one (because I couldn't and wouldn't afford the expense of a new one) and it never was right after that, always had a vibration. Also, the power steering rack failed at about that same mileage even though I had used synthetic fluid in the power steering as well. The transmission, using Lexus fluid, failed at 150,000. The only major component that didn't fail was the engine which was running perfectly. I have always marveled at people who say they get 200,000 out of any car without major rebuilds. I would have taken a 2003 Acura MDX to 200,000 but the engine started filling up with oil around 125,000, meaning that the level increased while driving, and by 157,000, it had lost so much power that it would barely run. That engine had had synthetic oil for 100,000 of those miles. Also, by that point, the steering rack was worn out totally and had lots of play in it which made driving a chore. I had actually replaced the p/s fluid several times and the fluid was pristine. Still wore out. The transmission and differential were still sound. Other problems included no rear a/c and the interior lights would no longer work. On the opposite side, I had occasion to drive a mid 90's Honda Civic that had never had the p/s fluid changed or anything other than oil changes and it's steering was just fine and it seemed to run generally very well. Way back in the 60's, I knew a farmer who got 200,000 out of 1961 Pontiac driving on gravel roads a lot. His car lasted longer than any of our Cadillacs did. It totally depends on the car and maintenance, but doing all the proper maintenance and even running premium fluids does not guarantee longevity.
