20,000 on the tires it started..... 58000 on the shocks... 2001 will be changing out the shocks in the next few months. Not to worried about it because for the last couple years I have been averaging about 100 miles a month..
Had no problem with stock shocks and Goodyear RTS tires. At 38,000 I changed to Monroe Sensa Trac shocks and Dueler Revos and had the alignment checked. I have had problems ever since.
Around 30k the stock GY started cupping. Changed them out to Revos, at around 40k. Did notice tires starting to cup again around 60k. So I changed the OEM shocks to RSX17000. No problems since, and I currently have 70k on my 04 Adrenalin.
From new I notiiced the wear on the front tires. Had the tires rotated to the back and replaced the stock shocks with monroe reflex shocks and have not noticed a problem with the front tires.
I've had goodyears put on at 7,000 miles after firestone recall. I still have them with the oem shocks at 40,000 miles. I just changed shocks to reflex 100 miles ago. I have never had cupping problems.
I had it on the OEM tires. Replaced them about 35-40k miles. I now have almost 80k and just starting to show a little wear(not enough yet to call it cupping for sure). I replaced the shocks at about 60k. I'll probably by another set of wheels and tires when I get home in November -- I want hub centric (or at least lug centric that can use the adapters to center them on the hub), unlike the ones I have now. My son is probably putting tons of miles on the ST since him and his wife find it better for hauling their new baby around thatn her Supra and his ranger ext cab so the tire wear will be more evident when I get home.
Luckily, I've never had the problem on my '05. I'm right at 50K and I have the original RT/S tires and they are still in great shape. That said, I don't really like them but I won't buy new ones until they wear out or cause trouble.
Cupping started at 4,500 mi on my '03. It got really bad at 13K, and tires were replaced shortly after by me because Ford refused to do anything about it past 12K (even though they clearly stated the problem at 4,500 mi).
Mine have been cupped since I got the truck with about 35,000 miles on it. I replaced the shocks but I think the damage was done on the stock GY tires. I'm thinking about getting wheels, tires and alignment when I get home next year and I hope that takes care of it. It drives me nuts!:angry: