Nothing. I would actually, honestly expect at least something to go wrong on so old car with so many miles, I never had better car even though most of my previous cars (before I purchased my first Lexus) were younger. Car is unbelievably reliable.
Some would ask... how many parts have You replaced? Not a single one of them.
Vehicle is worth every penny and more. It is just great. It practically never breaks. Engine, transmission and whole drive train is simply "bulletproof"
Thing such as window regulators, switches or other frequently used mechanisms should eventually go wrong over time. NOT ON THE LEXUS! I have owned at least 7 Lexus's in the past and I don't think I will ever want another car. You got much more for Your money than You would ever expect.
Many thinks that Lexus style is to conservative. Mercedes, Audi or BMW might look more modern, but it doesn't even comes close to Lexus's reliability, price and overall quality.
I have a 91 Lexus LS400 and I have to agree. I call it a "Trooper" because it's reliable and tough like a trooper or tank. It lets me know when it needs some attention, but will endure the stretch, without rebellion until I can have her properly serviced. This is my first Lexus and I bought it with a 109,000 miles. There is an 80-90% chance my new car will be the new GS or other Lexus model.