Well I'm doing just that. Doing a little preventative maintenance on the coach. Replace the air-bags (old ones starting to show signs of slight cracking). Replace the old Bilstein shocks. One huge problem with the Spartan IFS is the cracking and deteriorating of the ball joint boots. To top it off the ball joints are "non-greasable". Tried to order new ball joint boots and they are not available seperately but you have to order complete new ball joints. Uppers close to $200.00/each and lowers almost $450.00/each. The thing is mine are still tight with no signs of wear. So first thing I did today is drill and tap the body of the ball-joints 1/4" NF thread and install grease fittings. Now they take grease. The next thing I am going to do(and I think there is a market for this) is design and make molds for pouring urethane boots for the upper and lower ball-joints. I think that even if someone was to replace the ball-joints with new, the best thing would be to discard the poor rubber boots and install the urethane ones. Also modify the joint to take grease fittings right off the hop.