Oil Leak After Extended Driving in Cold Temperatures

2010-2013 Chevrolet Malibu; 2010-2014 Buick LaCrosse, Chevrolet Equinox, GMC Terrain; 2011-2014 Buick Regal; 2012-2014 Buick Verano; 2013-2014 Chevrolet Captiva Sport; equipped with the 2.4L engine (RPOs LAF, LEA, LUK)

Determine if the oil leak is the result of a frozen PCV system by inspecting the PCV system, dipstick, and engine oil fill cap for signs of ice, moisture or sludge build up. If a leaking rear main oil seal is found in warmer climates, this information does not apply. If a frozen PCV system is found, follow these steps:
  1. Check for proper thermostat operation.
  2. Remove the cam cover, inspect the PCV baffle inside, and replace the cam cover if obvious sludge buildup is present.
  3. Clean any ice/sludge/water/carbon out of the PCV pipes/hoses, the PCV nipple on the cam cover, the PCV orifice between the #2 and #3 intake runners (use a 1/16 inch drill bit), PCV orifice in the head and the throttle body. Also inspect the related PCV hoses/connections for potential damage
  4. After allowing the engine to idle at operating temperature for at least 15 minutes, turn off the engine and drain the engine oil for at least 15 minutes to remove all oil and condensation/ water from the crankcase.
  5. Repair any oil leaks that were induced as a result of the frozen PCV system and excessive crankcase pressure
Check for a leaking rear main oil seal

Clean the PCV orifice (arrow) between the #2 and #3 intake
runners using a 1/16-inch drill bit