Air shock replace with air bag

I have the same problem with my 2000 montana.The head gasket of my pump & compresor need to replace but when I ask GM dealership I was quoted $600. so I replace the air shock with regular shocks and installed air bag kit. I save $400. I'd been driving my montana for two years now and got no problem. better than original shock system. specially if you have heavy loads.

Can you tell me more about the kit? it sounds liek an interesting alternative...

yes, I got it from Canadian tire store. you could also order that in any automotive store. it's easy. lift up the rear of your van make sure you have it in scured jack stand at the frame. undo the bolt of your rear shock (bottom bolts only) bolt both side left and right. slowly lower the whole axle system thats includes your wheels.if you have no room remove your tires. make sure that you don't stretch your brake line. when axle asembly is lowered, your coil spring is lose, then you can cut the rubber pumper pointing down, install air bag kit. follow instruction manual. good luck!