I used to run BFG compTA HR4 tires sized 225-70HR-15 on my 1979 G20 conversion. ran them crusing the German Autoban at over 100 mph. They stopped making that size in the 'H' rating so I switched to a 245-60-15. Yes its a lot of tire but the van isn't stock either to run those speeds.

 

We've used Michelins as well on both 2000 Express 1500 conversions BUT
1) Seek replacements after 4 years even if they are still OK
2) Do not run them underinflated

 

I'm running them at around 40 PSI.

Why look for replacements in 4 years?
Do they suffer badly when underinflated?

Thanks!

 

I have 4000 miles on my new Firestone Destinations; a lot of miles for me, but it includes driving from San Diego, CA to Pittsburgh, PA for the summer. I had the alignment done when I bought the tires. The tires don't show any wear but they frequently "sing" at highway speeds on some pavement, which can be annoying.
(The door sticker says P235/75R15, which is what I've been using.
I went with Firestone Destination, an XL 60,000 mile tire. At 99,000 miles now, I doubt I'll put 60,000 miles on them. Our Scion xB gets more than twice the MPG, so the van is only driven when necessary.)

 

Blowouts in a van are a unique experience. I STRONGLY SUGGEST if you have one to ignore your urge to touch the brake pedal(the back end will try to come around and then you WILL roll the van). Let off the gas, listen to the tire coming apart and tearing up body work, but DO NOT HIT YOUR BRAKES until almost at a stop. Ask me how I know(didn't roll it but almost). Glad I drove cars sideways in my youth and did NASCAR driving at Richard Petty's school. You can feel what the vehicle wants to do next.....

Due to our climate(extremes of hot and dry) and occasional exposure to higher-than-normal ozone, we've seen sidewall cracking and had a blowout for "no reason" on one tire that had about 40K miles on it at about the 4-1/2 year mark. Hence our 4 year rule, no matter the miles on the tire.

Underinflation = fast heat buildup in your tire = tire failure soon.
Wife had a back tire(passenger side rear) blowout at 70 mph on I-10 leaving San Antonio due to underinflation. My son had noticed it "needed air" but air was not put in it before she left. She followed the "no brakes" rule when it blew out, survived but hated the noise while slowing down, and AAA Road service swapped the spare on for her. Tire was destroyed, aluminum rim had marks but was OK.