I've replaced lifters and cams on these with miles as low as 50k and as high as 160k. A few months back I had 2 6.2's in the shop at the same time for lifters and cam, one had ~75,000 miles and the other was pushing 120k. The funny thing is that on both of these neither had a failure on an AFM cylinder. I had a 5.7 Ram in the other day with 48,000 miles that need lifters and cam.