This is what is recommended... I have changed a couple belts at 60,000 some belts were really bad and some were ok but all of the tensioners were extended as far as possible... Thus saying that at some point if they kept on driving there would not be that much tension on the belt resulting in the belt skipping a tooth or more.. Which could be bad depending on the situation..... Also the cam/crank seal/s and water pump need to be replaced at this time as well.