I installed Synergy Ball Joints, Tie Rod, & Drag Link on a 2010 Jeep Wrangler in 2015. I had less than 18,000 miles on the Jeep when the non- serviceable ball joints were already bad. The non-serviceable tie rod and drag link ends were getting sloppy. These parts must be able to be greased or they will fail when used under off-road environments. I installed these parts and it is now 2022 with over 31000 miles, mostly off road in the Arizona, California, and Nevada deserts. If you decide to use these replacement ends, Synergy has a fitment chart on their website. For my Drag link, it takes a 4139L on the driver's side and a 4131L on the passenger side. For the Tie Rod, it takes the 4139L on the driver's side and the 4131L on the passenger side. The Drag Link is 8001 and the Tie Rod is a 8002. Just make sure you grease these on a routine basis when used off-road a lot. Synergy recommends their own grease, which if I didn't have any, I would use that. I had a stock of Chevron Ultra Duty EP that was used on Crawler Crane rigs.