Replace Part#: 5038784AD, 5038686AA 5038784AA, 5038784AB 5038784AC, 53021572AA 53021720AA, 53021720AB 53021720AC, 53021720AD 53021720AE Fitment: Chrysle.r 300 2007-2010 Dodge Challenger 2008-2021 Dodge Charger 2006-2021 Dodge Durango 2004-2005 Dodge Magnum 2006-2008 Dodge Ram 1500 2003-2008 Dodge Ram 2500 2003-2010 Dodge Ram 3500 2003-2008 Jee.p Grand Cherokee 2006-2010 2018-2021 Ram 1500 2021 Ram 2500 3500 2011-2018 Symptoms When the plunger inside of a lifter fails, it'll fail to maintain oil pressure and will remain in a collapsed state at all times, the lifter will fail to take up lash in the system, which causes parts inside to hammer against each other during initial contact. This hammering manifests as a very noticeable tapping that increases in volume and frequency with engine rpm. A bad lifter will throw off the affected cylinder's ability to move and burn air and fuel, which will typically lead to spark plug fouling and a miss on that cylinder. Consequences A collapsed lifter puts a great deal of stress on a vehicle's valve train. Collapsed lifters can easily bend pushrods, which will subsequently fall out of the space between the rocker arm and the top of the lifter. Once a push rod falls out of the space, the very least you can expect is a dead cylinder. Worst-case scenarios include broken rocker arms, broken valves, cracked heads, a damaged cam or complete engine destruction.