Most manufactures state that rustproofing is not necessary, but....
I feel it makes a HUGE difference in rust-belt areas like Cleveland. I am in the Northeast Ohio area and had my 2006 TJ rustproofed when new at Ziebart. After 98,000 miles and many winters with tons of road salt, the undercarriage still looks great.
Same with a 2011 JK which had Ziebart when new, and now has 42,000 miles and again, the undercarriage looks great.
I highly recommend Ziebart. I got just the undercoating, not the full rustproofing which consists of drilling holes in doors, etc.
2011, 2-Door Rubicon
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