When I worked for Dana Corp on the 2cd gen Excursion, which turned out to be a stretch Lincoln Navigator, Ford's standard design life was 150,000 miles. I should have said that the shocks for a V6 sport have white markings, some have paint spots, some short painted stripes and apparently some have round stickers. The important thing is that they all be the same color. By what I have read is that the Bilstein's on the rear are out. Our LS has 220,000 miles on it, the previous owner (of 16 years) had a long (about 150 miles) commute on the PA Turnpike, didn't drive on snow days, parked in the lower levels of a garage at work and in the garage at home. The cars only 3 misfortunes is that he had a large dog, his wife hated it (and the drivers door shows it), and it now belongs to me. The ride is still firm, it does not bounce and I think I wasted money on those 2 shocks, but the front suspension was apart anyway so.... There is a transition road from the westbound turnpike to the NE extension marked for, I think 45 MPH, I routinely take it at 70 with the LS and the Escorts, though with the Escorts it take more muscle.