pull a plug and take a look at it's condition - they normally will last but it depends on the fuel, when I upgraded my coil and wires I replaced the plugs but they didn't look bad when I pulled them at about the same mileage you are now. maybe run injector cleaner through the system.
seeing that you're in a winter area - I'd also check
brake pads
if you have a lift - check all your bolt torques
Belt - cracks or abnormal wear
check the condition of your battery cables and body grounds make sure they all look clean no rust etc...
may even have your battery tested - I didn't look to see what year your Jeep was.
Throttle body - mine gets dirty fast - I'm beginning to think it's the CAI causing this - my buddies doesn't seem to get as dirty with his stock filter but he also doesn't drive as many miles.
have fun, cheers :beer: