Treacle JK/JKU Heavy-Duty Ball Joints are engineered to handle the increased load caused by oversized tires and offset wheels. FITS:• JK Wrangler (2-door) w/ Dana 30 or 44 axle• JKU Wrangler Unlimited (4-door) w/ Dana 30 or 44 axleINCLUDES:• Upper ball joints w/ knurl - pair• Lower ball joints w/ knurl - pairUPPER BALL JOINT FEATURES• Extremely hard sintered wear bushings to handle extreme side load demands w/out failure• Magnesium Phosphate coating to inhibit corrosion throughout• Heat treated 4140 chromo ball/stud & 1045 carbon steel housing• Factory-style serrated flange nut & grease fittingLOWER BALL JOINT FEATURES• Hard alloy tool steel slotted wear plate for ball/stud to socket wear protection• Wear plate features grease channels for increased flow through entire joint ensuring longevity & predictable operation• Magnesium Phosphate coating to inhibit corrosion & friction throughout• Heat treated 4140 chromo ball/stud• Huge 30mm (1.18”) ball• Factory style serrated flanged castle nut• Ball joint pre-load adjustability provides the end user w/ near effortless wear adjustment (kit includes Preload Adjustment Tool)• Low-profile single lip dust seal eliminates torn conventional dust boot concerns• Adjustable ball stud retaining ring for accurate initial & future preload adjustments that can be done w/out any axle disassembly• Adjustable preload can be performed w/ simple hand tools• Adjustable end cap w/ two zero fittings allow greasing access from either side w/out axle shaft removal even w/ larger RCV shafts• Dual helical grease grooves machined in the retaining ring allow spent grease to exit through the low-profile seal• Low-profile seal prevents contaminants, while allowing spent grease to evacuate from the ball jointNOTE: • We recommend Ball Joints w/out Knurls (# 3442002 or # 3440000) as they will not score the inner knuckle & open up the bore. • We also offer Ball Joint w/ Knurls (# 3442022 or # 3440020) for ball joints that have a loose press fit in the inner knuckle due to repeated ball joint replacement or if knurled ball joints have been installed in the past.INSTALL TIME: 4 Hours