Excitement for the week - tire blowout

Not sewing machine related, but we were on a camping trip with our pickup truck and camper the last several days. Coming home on the final 100 miles of our 1200 mile trip we had a blowout on the left rear. A loud motorcycle was just passing us on the left and we heard a very loud *bang*. We figured it was the m/c but all of a sudden our truck started swaying. My son was driving and he got the truck pulled to the side without incident. Here's the damage:

So today I head to the local Les Schwab store to see what they can offer. The tires on the truck have 24,000 miles on them but they are 8 years old (yeah, so I don't drive the truck much - it's a '96 with 104k miles). The tech mentioned that RVs should get new tires about every 8 years. Not sure I believe him. I'm thinking the sidewall was just weak. Anyway, the salesman gave me a good deal on some new Toyo H/T tires (not that it makes spending $635 much easier). He said the Toyos should have a stronger sidewall due to different construction. I guess we'll see.