FORD TSB's 97-17-13 & 14 BOTH REFER TO NOISE FROM REAR HEAD RELATING TO CARBON (OLDER APPS), CAMSHAFT FRICTION GEAR & SPRING NOISE; AND HYDRAULIC LASH ADJUSTER (HLA) NOISE. IT'S A PRETTY INVOLVED PROCEDURE & COSTLY. CAN ANYONE TELL ME WHAT TO EXPECT IF THIS NO... Login to read more.