Tirerack.com might have it too.
But what the hell are you going to do with 20" rims on a Trooper?
- Coupled with low profile tires they will make your truck look like you're trying to rice it out
- Chrome 20's will make it look like you're bling-bling'in which is laughable because it's a TROOPER.
- 20" rims will likely more than fill the wheel well unless you lift your truck
Stick with some nice 17's.. 20 is waaaaay too big for that vehicle IMO