1. Check alignment.
2. Check Tire balance and bent wheels
3. Check Track Bar bushing and rod end
4. Check control arm bushings
5. Steering stabilizer
Being you have the common 40-45 mph wobble if the rig is not wandering or pulling at other speeds your alignment is probably okay.
Jeep tires go out of balance all the time, but they are out of balance at all speeds, not just 40-45 mph
Track Bar bushings on the axle end are famous for causing DW. Also check the frame end for looseness. No play should be felt.
Control arm bushings can go out really quick if you ever hit the trails. Just a little play there is gonna give you the 40-45 mph boogie-wooky you have.
Don't spend fortunes on a steering stabilizer. Monroe makes one for 30 bucks that works great. Pep boys sells them. ST2928 part number IIRC But remember, the stabilizer is only a mask if you have other issues. Being you have a 5 year old Jeep just replace it.
Track Bar issues and ruined stock control arm bushings are the number one culprit. And absolutely a 2006 Jeep can get DW fast if any of those components are bad. Other issues that can cause it are the ball joints on your knuckles and the wheel bearings.
2006 Solar Yellow Rubicon Unlimited
Jeep Club Member #1340
6 Speed, Hardtop
Mods done: Hurst tee handle, cheap hand throttle, Rokmen Merc front bumper, Warn 9.5 TI winch with 3/8" X 100 worth of Viking yellow rope, DPG OME Ultimate with JKS ACOS up front, Kilby Gas Tank Skid, Kilby Steering Box Skid, Jeep Medic Belly Up, Skidrow Engine Skid, Rockcrusher Diff Skid in the rear, Warn Diff cover in front, , AR Outlaw II's and MTR 12:50/15's, Homemade rear Bumper, Cheap Cobra CB, Puma OBA, Sirius Radio, Locker Defeat, Rockhard cage, Rockmen short corners, homemade tire swing/tailgate hinge affair, Airlift air bags on the rear- - - - - - and more to come!