3xb18

I have a 2006 Nissan Sentra with a 1.8 in it It has 120k on it I called nissan they said the 120k service is 1600 dollars and involves timing chain/belt, serpentine belt.anyone that could do this on the side, Not a back yard guy that has done one before.. I have done timing belts in the past but I drive this car at least 400 miles a month and sometimes 500 miles a day I want to know it will not leave me stranded ..thanks in advance