How big of tire rims and tires will fit on an extended 1997 tacoma?
I would suggest contacting a local tire and rim dealer, who will be able to tell you max sizes and what has worked for them with customer's vehicles in the past. Probably no reason you couldn't go as high as 20" rims with the right tires, but you would want to change your braking system to compensate for the increased rotating mass of the larger wheels.
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