2009 Subaru Impreza Owner's Manual - Page 335

11-20 Maintenance and service Drive belts Check the deflection of the drive belt and if there is any looseness, cracks, wear or unusual noise on front side belt we recommend that you contact your SUBARU dealer. Continuing to use the vehicle with the belt outside of the specification may cause the engine to malfunction and the above components to malfunction. To check the tension of the front side belt, place a straightedge (ruler) across two adjacent pulleys (alternator and crank pulley) and apply a force of 22 lbf (98 N, 10 kgf) midway between the pulleys by using a spring scale. Belt deflection should be the amount specified. If the front side belt is loose, cracked, or worn, contact your SUBARU dealer. in (mm) Deflection New belt A 0.28 - 0.35 (7.0 - 9.0) Used belt 0.35 - 0.43 (9.0 - 11.0) Manual transmission oil & Checking the oil level 1) 2) 3) 4) 5) 6) A) Power steering pump pulley Front side belt Alternator pulley Air conditioner compressor pulley Rear side belt Crank pulley 22 lbf (98 N, 10 kgf) Non-turbo model 1) Yellow handle CAUTION The drive belt, which runs in conjunction with the following components, must be used within the specified deflection. . Power steering pump pulley . Alternator pulley . Crank pulley The rear side belt is a stretch-type belt, and the deflection and tension do not need to be checked. If there are cracks or wear confirmed on the belts and a squeaking sound is heard from them, contact your SUBARU dealer. Turbo model except WRX STI