Recently picked up a '02 Grand Vitara Limited, and was planning on using the same 15" Tracker wheels that I ran on my last Vitara, along with 235/75R15 tires, preferably without lifting it.  Just tried to bolt them up, and not even remotely close to clearing the brake calipers.  I _thought_ I had ZR2 wheels, which I bought specifically to run 15s on that other Vitara, which was a '02 base model, but now I'm suspecting that I bought Tracker base alloy wheels.  I did find that adding a 2" spacer behind it gets it close enough to fitting that I would just have to skim the high points of the caliper to fit.  But I don't yet have tires to fully test this out. 

Is there a difference in the way that 15" Tracker base wheels fit compared to a ZR2 base wheel, in that a ZR2 wheel might actually work here without spacers?  This is the wheels that I have -

Wondering if someone else has gone down this road - tracker wheel plus 2" spacer, 235/75R15 tires, before I drop hundreds on new tires to find out it won't clear.  Alternatively, does it work with actual ZR2 wheels vs the wheels that I have? 

As you have discovered, 15" rims don't clear Grand Vitara brakes, although they may clear on the base models, some of which use a smaller brake assembly.

As far as I know, all the Tracker models were supplied with a 15" rim, so regardless of whether you have the base model alloys or the ZR alloys, you'd be in the same position - the rim will still be a 15 and too small.