Yesterday, (Sunday of Labor Day weekend) we were 550 miles from home and needed to get a jump on our southward trek in order to make appointments set for Tuesday in Tucson.  But before we headed out this morning we took another crack at the Slickrock Foot trail because we’d been shut out the day before by thunderstorms.

We managed to cover the entire 2.4 mile trail in about 90 minutes, and it was well worth the effort.  We got some of the best views yet of the Needles rock formations that give this district of Canyonlands its name, and several dramatic overlooks into canyons near the Green River. Still, when we got back to the campsite we discovered we were late to depart, since checkout time for Squaw Flat is quite early at 10 a.m. Usually checkout is at noon.  Hustling everything together, we managed to clear out and be on the road about 15 minutes after getting back to the site.

On the way in or out of the Needles you will pass the Newspaper Rock State Historic Site.  There are actually several “newspaper rocks” in the southwest, including one at Canyon de Chelly that we’ve visited before.  They are simply large flat areas of sandstone covered with centuries of desert varnish and riddled with dozens of petroglyphs.  We’ve seen a lot of petroglyphs but these were still remarkable for their clarity and descriptiveness.  In some cases it’s anyone’s guess what a petroglyph means, while others are perfectly understandable as drawings of commonplace animals, events, and humans.  Take a closer look at the photo and decide for yourself what centuries of rock artists were trying to convey.

Other than that, our drive for the rest of the day was uneventful, the way you want things to be when you are hauling a trailer long distances.  We made a quick stop in Blanding to dump the tanks and refill the fresh water, and encountered some thunderstorms as we drove through the vast Navajo Nation in northwestern Arizona.  It was still raining when we pulled into the Bonito (Coconino National Forest) campground next to Sunset Crater Volcano National Monument just north of Flagstaff AZ that evening.

This was to be our last night on the road, so we had let some supplies dwindle away, including milk and most fresh vegetables. Eleanor made a salad of what was left, and spaghetti with meatballs, and we settled in for the evening while the temperatures outside dropped into the low 50s.  I was thinking how novel it would be to need blankets on the bed at night for this one night, before returning to the desert heat on Monday.  And it was indeed a pleasantly chilly night.

But our plan to make Tucson on Monday was foiled.  We left early and were descending down the 6% grade about 50 miles south of Flagstaff when suddenly we began to hear a “thwap-thwap-thwap” noise.  That’s never a good sound.  Neither the trailer’s nor the Mercedes tire monitor reported any loss of air pressure, so I was fairly sure it wasn’t a blowout. Still, it had to be investigated immediately.  Traffic was heavy, but I managed to get the Airstream off to the breakdown lane within a half mile and from there Eleanor and I searched for causes.

We didn’t find anything. The Airstream was secure, the car looked perfect, and yet … upon driving away, the sound returned.  I took the next exit and found a dirt lot where we could search further.  Eventually we found the cause: a 1″ wide strip on the inner edge of the right rear tire of the Mercedes had neatly peeled off. In other words, we had a tread separation.

This is a sadly familiar situation.  We had numerous tread separations when we were running various brands of ST (Special Trailer) tires on the Airstream, but that problem was resolved when we switched to Michelin LTX Light Truck tires.  (They still look like new, by the way, with hardly any visible wear after 21,000 miles!)  But I hadn’t expected to suffer this type of failure on the Mercedes.

We’re running the factory-specified tires on the Merc, which are Goodyear Eagle 275/50 R20 RunOnFlats.  Our first set was replaced at 34,000 miles, which I was told is “pretty good wear” thanks to the highway miles we tend to cover.  The current set has 32,000 miles and I had already made some inquiries about replacements since I figured they had only about 2,000 miles left in them.  All of the tires have tread above the wear bar indicators, have been rotated regularly and kept at proper inflation, and are evenly worn, but the one that failed definitely has a little less tread than the others.  That doesn’t excuse the failure—it simply should not happen with usable tread still on the tires, even with the added load of towing. I’ll be looking for a different brand this time.

So let’s look at our situation:  (1)  Tread separation while towing and we have no spare tire (this car comes with Run Flats and no spare carrier).  (2) It’s Labor Day, so there are no open tire stores.  (3) We’re in a part of northern Arizona where there are few services and no alternate roads to the busy 75-MPH Interstate.  (4) Our car takes an odd size tire so a call to Roadside Assistance probably wouldn’t be helpful.  The tire will have to be ordered.  In short, we found ourselves in the “nightmare scenario” that made me hesitate when I first bought this car.

Although the tire was holding air, there was no way it was going to be safe for another 200 miles at Interstate speeds and in desert heat.  Our conclusion was to find a place to park for a night or two, and wait until a set of proper tires could be ordered in.  So we pulled up the Allstays app on the iPhone and found a nice RV park in nearby Camp Verde AZ, and gingerly towed the Airstream at reduced speeds another 16 miles down the Interstate to our safe haven.

My plan is to call the tire stores first thing tomorrow and order in what we need, with the hope of getting back on the road by Wednesday afternoon.  Prescott AZ is nearby, with plenty of choices, so I’ll be over there tomorrow once someone tells me they can get us five appropriate tires.  I say “five” because I have a spare Mercedes rim back at home, and one tire will be mounted on it.  The spare will go in the Airstream’s tire carrier, replacing the Airstream spare.  Since we switched to Michelin LTX tires on the Airstream two years ago (in other words, real tires instead of that ST-class junk the industry favors), we haven’t had a single puncture or failure, so I don’t mind not carrying a spare for the Airstream.  Besides, the Airstream can be towed on three wheels, and the car can’t.

And so our trip has been involuntarily extended.  Things could be worse.  We’ve got a friend to visit in Prescott.  I’m working on the Winter magazine from here, using the campground wi-fi, and we had a nice swim in the pool, and Eleanor is getting the laundry done.  When we finally do get home, we’ll be caught up on a few things, rather than coming home to a pile of work.  Other than having to reschedule appointments at home, this may turn out to be not a bad diversion.