Oil Cooler WRX FA Pad Shims This sensor measures the oxygen

This sensor measures the oxygen content in the exhaust system post catalyst

: 16102AA380

EXTERNALLY ADJUSTABLE PRELOAD

but the factory rubber damper is also tuned for a narrow rpm range and standard engine component weights and power levels  Fluidampr balancers use a viscous fluid to work across the full rpm range and with increased power levels

Forester MY04-13 (all models)

Oil Cooler WRX FA Pad Shims This sensor measures the oxygenReplacement FA20F water oil heat exchanger (oil cooler). Located between the oil filter and timing chain cover. Supplied with sealing o ring. It is suggested that the oil cooler be replaced after a bearing failure due to the difficulty in completely removing any metal debris from inside the cooler. Manufacturer Part No: 21311AA180 What it fits: WRX MY15 19 Forester XT MY14 18