Nothing at all (25k miles).
All around excellent design - years of minor improvements pay off handsomely. The only minor gripe I have is that the Air Conditioning is a tad weak for Arizona - definitely needs dark tints for the desert.
The air is weak for the south and I have had problems with oxygen sensors (check engine light) starting at 40,000, as well as the ABS light coming on. I have 50,000 now, and none of this is covered under the warranty.
I have a 1998 Trooper with 62k miles and live in NYC. the check engine light produces a code of O2 sensors and all have been replaced. The light still comes on a week or so after reset.
I have the same problem with O2 sensors. I've replaced mine, and it has made no improvement. It still runs though... except for that time the fuel float got jammed and I ran out of gas.
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