Thanks to everybody for the advice and enlightenment. For the most part, you have all reinforced what I was thinking. Just wanted to make sure I didn't miss anything.
Actually, the evaporator itself is probably not leaking. The service adviser described the leaks as being in the o-ring joints that connect the several lengths of aluminum tubing connecting the front condenser to the rear evaporator setup. Those joints were all too corroded to separate. Presumably the tubing connections at the rear evaporator were similarly corroded. Of course the dealer's solution is to rip it all out and replace it. And from a dealer's -spare no cost to the customer- perspective this makes some sense. When I googled the problem, I saw some photos that showed the couplings are aluminum, tapped and held together with steel bolts. As you would expect, a little road salt would make the dis-similar metals fuse into an inseparable mass. It would take mucho time, skill and tools to replace just those joints. My wife says she doesn't care about the rear air conditioning, now that the kids left the nest. So I'll probably plug or bypass, as appropriate, the lines to the rear. To keep the records accurate, I can't speak extensively about Toyota, but this Sienna has been remarkably trouble free for the last 175,000 miles. The four Mercedes diesels I've driven over the past 30 years have never had an air conditioner failure. The only significant air conditioner failure we have ever experienced was in a Dodge Caravan my wife previously drove. Thanks again for the advice and help, Ned Kleinhenz _______________________________________ http://www.okiebenz.com To search list archives http://www.okiebenz.com/archive/ To Unsubscribe or change delivery options go to: http://mail.okiebenz.com/mailman/listinfo/mercedes_okiebenz.com