1999 Toyota 4Runner Limited review from North America

I purchased the 4runner in April of this year, but it has been making a knocking noise in the motor. I have taken it to the dealership 5 times. The first time they replaced the air compressor. The second time the oil was changed with heavier oil, and bearings greased to try and stop knocking. The third time the harmonic pulley was changed. The forth time I was told to come by and let a service tech ride with me. He called in the regional tech to come look at it and then they told me there was nothing that could be done. They say it is characteristic of the vehicle. Then I took it to another dealership and they changed the water pump, timing belt and two other pulleys, but the knocking noise still exists. I am trying to find out if anyone else has had this problem with the 4runner.

I love this vehicle, but just want it fixed. I would like to know anyone else has run into this type situation.