just recently when i start my car cold i hear my lifter or two making a tapping noise only when the car is cold, never after it warms up, the noise last for about 5- 8 seconds it sounds like a lifter is bleeding down then finally fills up. im running 10 30 weight oil, never did this before only when temps went into the 30's. should i use a different oil or readjust my rockers, i m using a billet roller from pte, t d rollers. what should i do is this not a big deal . please help