8000? hmmm...Changed mine after the first season, had 9-10k on them, showed them to my mechanic and he said that he wouldn't have changed them. Have gone 2 seasons on this set, will be changing them before next season just because!Service manual shows replacement at 8000 miles. Standard condition plugs are NGK DPR7EA-9 or ND X22EPR-U9. Gap is .8mm-.9mm/.031"-.035".