I run 4.56 with my 35's and my Jeep has a ton of heavy stuff bolted to it. Off-road no problems. On road, I do have to down shift on some hills, but its not bad. Thus with your 33's you could go either way, If I had to pick though, I would go with 4.56's for two reasons: 1st, if you ever decide to run bigger tires you will be okay and 2nd, if you do add a lot to your jeep then it will help to counter that for your on road driving. And to add even more I drove a buddy's with 33's and 4.11's and it was fine on the highway, even did great with cruise control on hills.