I have a 2000 nissan xterra with 92000 miles. I get the oil changed every 3000 miles since I've bought the car in 2000. I've noticed that when I travel under 40 miles per hour I hear no noise. But when I travel over that milage I hear the tapping noise. It will go away if I travel around 25 miles per hour for a mile to two. What can I do to eliminate that noise?

 

Have you by any chance changed brands or grade of oil, or oil filter ? If not, I would have my oil pressure tested, especially at various speeds, unless you have a reliable oil pressure gauge in the dash. Did this just suddenly happen, or has it been gradual?

 

I'm due for an oil change within the next 400 miles. The mechanic that I take it to has use the same brand of oil as in the past. It just started happenning.

 

I'd have mechanic check oil pressure with a known good gauge, with engine warm, at operating temperature, then determine where to go from there. A simple thing to try would be a heavier oil. The reason I asked about changes in brands of oil in earlier post, was because I sold a car to a relative one time, that I always used castrol gtx in. They had the oil changed soon after & the car started using oil badly. ( 1 qt about every 50-60 miles ) They changed it again, same result. Then I found out that the garage was using re-cycled oil, that the well known oil company swore was as good as or better than other oils.I told them to try Castrol again just for fun, and oil consumption was back to normal.