I've done searches all over the net and can't find an answer to my question. My daily driver is a '97 Expedition I purchased new. It has 160,000 miles on it and I've never replaced the original air shocks. I'm just wondering if air shocks wear out and/or go soft like standard shocks do? They still hold pressure just fine. Maybe I'm just feeling guilty since I've never had a vehicle this long without replacing the shocks.

Thanks.