First example of inferior quality were the front brakes. At just under 20,000 miles the rotors were warped beyond repair and the brake pads were worn out. Complete brake R&R about $650.00. As a side note my Taurus was replaced at 135,000 miles and had a brake pads installed at 90,000, and still had good brakes at time of sale. The front brakes on the Jeep are aftermarket and are still in good condition.
At 78,000 I noticed excessive coolant loss. It turned out to be the freeze plugs rusting out. Shop replaced with aftermarket plugs for about $350.00, but slight leakage began to occur within 1,000 miles, then at about 3,000 miles after the forward plug blew out suddenly, all coolant was lost and engine was shut down immediately. New dealer plugs installed by same shop seem to be holding... for now.
Current problem however is the front differential. It started making a buzzing noise at 60,000 miles that seemed to gradually grow in volume over time and miles. It was sort of a growl that increased with speed and diminished while slowing down. The front pinion bearing was replaced at about 80,000 miles. The race and bearings exhibited significant pitting. Well, here I am at 92,000 miles and the same noise is back. Haven't been to the shop yet but will soon.
This rig has had an assortment of weird problems too. For example, drivers side mirror delaminated and had to be replaced $500.00.