Being interested in tire upgrades, and understanding the metric sizes vs. the old style (33 x 12.50 / 15) I have done some research.

My 06 Fx4 SCAB came stock with 275/55/R20
which amounts to: 31.8" x 10.9" x 20
(conversion is available here in the forum and tire websites)
Costs between $130 - $220 each tire with worst case being about $1,000 - ALL 4 TIRES

Now... you level it out and want 33s....

305/55/R20
33.2" x 12" x 20
$285 - $400 EACH.... worst case about $1,800.... ALL 4 TIRES

That means you are paying $800 - $1,000 for 1.2" of tire.
I'm thinking a more aggressive tread on the smaller size may be the way to go.... any thoughts???

 

Depends on what you want. Be careful on the type you go with becasue not all MT's have a good snow/ice rating for you in PA.

 

That's the problem with 20" wheels. The prices go higher and higher the larger the rim, that's why I stuck wih 17s when I got aftermarket wheels.