HEARD LOUD TICKING NOISE COMING FROM ENGINE AT 86330K MILES. VEHICLE RIDE BECAME SOMEWHAT ROUGH. DIAGNOSED AT VOLVO DEALERSHIP AS BALANCE SHAFT BEARING "PART FAILURE". EST. TO FIX: ~$3800. VOLVO AGREED TO COMPENSATE FOR THE PARTS, APPROX $1500. BALANCE OF $2325.50 PAID BY VEHICLE OWNER. TOOK 1 WEEK FOR VOLVO TO OBTAIN PARTS AS THEY ARE NOT COMMONLY STOCKED OR WERE BACK ORDERED. ON LINE RESEARCH REVEALED THIS TO HAVE BEEN A PROBLEM WITH EARLY 2005 XC90 V8'S. WATER/CONDENSATION/VAPOR IS ABLE TO GET IN AND RUST THE BEARING LEADING TO ENGINE FAILURE. A TSB WAS ISSUED (? WHEN) FOR A FIX TO DRILL A "WEEPING HOLE" IN ENGINE BLOCK TO DRAIN WATER FROM THE BEARING. *TT