Our 2002 van has just been used for normal family duties and rarely is heavily loaded.
The front struts and rear shocks were so worn by 48,000 miles that the vehicle pitched all over the place.
I replaced them this past weekend (boy those front struts were a pain to get to the top mounts on!).
The rear has the factory air leveling system. Luckily Monroe provides an exact fit replacement which I bought for $85 for the pair instead of the factory part at nearly $200 each!!!! GM should be ashamed to be charging people $200 each for run of the mill air shocks which wear out so fast.
Does 48,000 miles seem like a short time to you folks?
John