biggest tire size?

[Riff Raff]

Stock '01 tires were 245/60/18, which is roughly 29.57 x 9.65. As Riff already mentioned the stock rims are 7" wide.

VT--- your numeric "stat's" are dead-on target IAW the Discount Tire website Info Center & Tire Calculator:

http://www.discounttire.com/dtcs/infoTireMath.dos

Other fun tire websites are www.1010Tires.com (my personal favorite for comparing 5 different sizes side-by-side); www.TireRack.com (great for individual tire weight in lbs); www.Tires-Easy.com (unbelievable selection at killer prices); www.OnLineTires.com (good selection with decent prices); www.Treadepot.com (oftentimes the frickin' lowest prices found anywhere in the USA, but somewhat limited on brands); and www.DiscountTire.com (link above) tire calculator for estimating your new "speedometer error" at various MPH travel speeds.

[VX KAT]

and the tire /rim calculator I like best....it's got the best visual interface IMO:
http://www.rimsntires.com/specs.jsp