Yes, our 20 yr old 36' diesel pusher (129,000 miles) needs new air bags. We contacted Spartan Chassis and they can get us the front bags and we have ordered 2, but they cannot get the back air bags. Suggested we try a forum to see if anyone in the RV world may be able to help. Spartan said these air bags in 2002 were made by Firestone. That part number is W013588959 for the back air bags. Would appreciate any suggestions. Thanks.