Jeep HD Knurled Front Ball Joint Set Dana 30/44 1 Upper 1 Lower Jeep TJ/TJL/YJ/XJ/ZJ (4120-04)

Replace your Jeep's factory ball joints with Synergy MFG's Dana 30/44 Heavy Duty Ball Joint Set. These ball joints employ a metal on metal design to improve durability and performance. A must for vehicles with lifts and larger tires. Get rid of that steering wander and play caused by loose or worn out ball joints.Fits:97-06 Wrangler TJ and 04-06 Wrangler Unlimited TJL90-95 Wrangler YJ90-01 Cherokee XJ90-92 Comanche MJ93-98 Grand Cherokee ZJFeatures:Compatible with all aftermarket axle shafts (including RCV) with no modifications neededFully Greasable metal on metal design for prolonged lifeBall Joint bearing surface area is considerably larger than stock due to elimination of the inner nylon liner for a longer lasting jointBall joint housing is manufactured from sintered graphite, bronze, and 1045 steel for a strong, smooth, bearing surfaceBall joint stud is manufactured from induction heat treated 4140 steel for maximum strength and smooth operationBall joint dust boot is made from wear/tear resistant black nitro-butile rubber (NBR)12 Month Unlimited-Warranty (see warranty information)Synergy High Performance Grease (4119) recommendedNotes:Metal on metal ball joints require a small break-in period of typically 100-500 miles to fully "seat" the bearing surfaces. During this time the steering may feel "sticky" or slow to "return to center". Once broken in, the steering will be smooth and tight.Knurled ball joints required when replacing knurled ball joints that have enlarged the axle end forging boresNon-Knurled ball joints recommended for replacing non-knurled ball jointsDue to these ball joints being tight tolerance, metal on metal ball joints, proper fitment is critical. Using the wrong style of ball joints can cause significant steering issues. We always recommend installing non-knurled ball joints until non-knurled ball joints are no longer a press fit into the axle end forging bores. If your axle end forging bores have been enlarged to the point that non-knurled ball joints are no longer a press fit, knurled ball joints are required.Use of the improper ball joint style for the axle housing voids our warranty. It is up to the installer to verify the proper ball joint style is being used.