Nothing that doesn't go wrong with any vehicle: muffler, shocks, fuel filter, brakes. (Note: When the fuel filter goes on a 1993 Tracker it goes suddenly, instantly in fact. If in doubt, replace it.) Apart from that my 1993 Tracker is by far the best vehicle I have ever owned, and I have owned over 30 vehicles. The only negative comment I have regarding this vehicle is comfort, or lack thereof, but the makers do not claim that it is a GT. so fair enough. My Tracker now has more than a quarter of a million Kilometres on it, and it shows no sign of quitting. I think it is one of those welcome anomalies, like the Plymouth 'slant six'.
No complaints that could be considered reasonable.
I just purchased a 93 Geo Tracker, and besides the soft top being in bad condition, everything else is good. I filled the tank for 10.00 with gas at 1.55 a gallon. So I am very happy with that. If anyone knows where to find a good soft top in Atlanta please post the info. I have great plans for this fun little Tracker!