Mine was very good when I got it and it started to knock or rattle just like my 2000 after about 2500 kms not as loud but same kind of sound. Truck seems to run fine, just bugs me that it does not sound the same as it did. Now have 7000 kms and still sounds wrong to me. I will try changing the fuel filter and see if it makes a diff. I run Howes meaner power kleaner every tank and average 15-16 mpg hand calc. Could be better I think.