There is the aluminum stuff, the copper stuff, the nickel stuff, and probably dozens more. What is the best for use under the Jeep where the salt water lives for 6 months of the year? Time to replace the control arms and do NOT want a repeat of what I'm going through now. My God! If I didn't know better I'd think the bolts are welded in! Any tricks? 145K miles on the originals. If I didn't have one clunking so bad I'd be tempted to leave 'em be. Whish I had a lift.