These simple tips will make your experience in and around 4EAT transmissions safe and profitable.

Changing the engine oil would seem to be such a simple procedure. Yet a mistake can yield catastrophic results. The transmission in the photo above was being replaced due to a differential failure. The differential failure was not caused by a part failure, but rather by operator error. The differential fluid had been drained during an oil service, rather than the engine oil. The drained fluid was not replaced, and a few hundred miles later, the differential was destroyed.

This error may have been caused by unfamiliarity with Subaru vehicles or    simple inattentiveness. In any case, it’s not a mistake any of us would want to make. Although we ran this information in an earlier End Wrench, seeing the destroyed transaxle drove home the fact that some technicians still need to be reminded of the correct service procedures.

When performing an oil change service on Subaru vehicles, don’t confuse the drain plugs and filters located under the vehicle. Subaru models produced over the past several years feature an under-engine cover. This cover greatly reduces the accumulation of dirt and grime on the engine and also reduces the overall coefficient of drag of the vehicle. However, it does limit the access to the engine oil drain plug and engine oil filter.

Items to remember when performing services on Subaru vehicles:

• The engine oil filter is located at the front of the engine.
• The engine oil pan and 17 mm oil drain plug are painted black and are located directly under the engine — above the under-engine cover.
• The engine oil dipstick is located under the hood, on the front driver’s corner of the engine.
• The transmission front differential is bright aluminum with a gold-colored 21 mm drain plug. This housing is bolted directly behind the engine and is filled with GL-5 gear oil.
• The differential dipstick is located under the hood near the firewall, on the passenger side of the differential housing.
• The transmission pan is black. Its 17 mm drain plug is located on the driver’s side of the pan. The drain plug is normally silver in color, but black drain plugs have also been installed on occasion. The transmission is filled with Genuine Subaru factory fill AT/PS Fluid P/N SOA868V9240.
• 1999 and later Subaru vehicles equipped with automatic transmissions have a screw-on filter on the driver’s side of the transmission. Do not confuse this with the engine oil filter. The transmission filter does not require service under normal conditions.
• The automatic transmission fluid dip- stick is under the hood, on the driver’s side of the car near the firewall.
• All three dipsticks have yellow handles for easy identification.
• Always confirm proper lubricant levels in each unit after performing any service.

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