I just bought my first Tracker and I love it. It is all stock and has been mostly towed. I am curious what the biggest tires that would fit in unmodified fenders would be? I have heard that some 30 inch tires would fit with now rubbing but that is hard to fathom. Just wanting a bit more grip for now, modifications to come..... for now just curious about tire size.

I ran my 235/75/r15 BFG's on 15x7" rims & stock suspension & only got a slight rub on the front plastic fender liner... just enough to knock the mud off. I've not heard anyone say 30's wouldn't rub at stock height, have heard of ppl having rub with 30's even with 2" lift.
Short answer: 235/75/r15

if you have a little money i would by the 2in budget lift off low range for $120 and some 30s. it looks really good and does really well in the woods and trails

Thank you both very much right now it has 205/65/15's and hwy tread... runs nice and smooth on the hwy  but I am getting ready to start water-fowling and being in the deer woods so i need a bit more grip in the fall wet season.

Thanks for your comments.... very helpful.

Next question where/how do I get a spare key for the 92 Tracker? I have asked all the key making places in town and no one can match it. Is there a way to use the vin# to get a key from Geo/chevy?

If you have a 2 dr., remove the passenger (right) door lock.  It should have a code number that your locksmith can use to cut a new key.  Had it done a few times and cost less than $20.  Good luck