Oil Capacity and Drain-Back Rate
This bulletin applies to 2020 Jeep Gladiator, 2016-2020 Grand Cherokee and 2018-2020 Wrangler vehicles, all equipped with the 3.6L Pentastar Upgrade engine, with regard to checking engine oil level after oil filling.
The customer may note that after an oil change, they check their oil level and it is showing an overfill on the oil dipstick.
The 3/6L Pentastar Upgrade engine typically uses a small oil pan for most applications versus the 3.6L Pentastar Classic engine, resulting in an engine oil capacity of 5 quarts for the Upgrade engine. Of particular note: The 3.6L Pentastar Upgrade engine has a slower oil drain-back rate.
After filling the engine to the correct oil capacity per specifications listed in the service information, the oil level may show a low condition on the dipstick due to the slower drain-back rate. This may prompt the person performing the oil change to add more oil. Engine crankcase overfilling can occur if not enough time is allowed for the oil to drain back into the pan sump. DO NOT add more oil than specified in the service information.
When identifying a 3.6L Pentastar Upgrade engine, the Upgrade engine has an EGR cooler mounted to one of the cylinder heads, and a variable valve lift (VVL) solenoid on the front of each valve cover.
Note an exception to the above information.....2016-to-current Jeep Grand Cherokee equipped with a 3.6L Upgrade engine has a unique oil pan size and configuration that provides an engine oil capacity of 6 quarts.