HEMI ENGINE AUTOPSY: THE REBUILD
After two decades of production, the third-generation 5.7 Hemi V8 has amassed a solid reputation as Chrysler’s bread-and-butter workhorse and high-performance platform. In that time, the company name on the Hemi V8 has changed several times (the Hemi is now a Stellantis product) but that hasn’t dented the third-gen Hemi’s destiny as the go-to heavy-lift reactor core for the Dodge, Ram, Jeep, and Chrysler nameplates. A continuous string of upgrades over the years has gradually improved performance and fuel economy, and now that many Hemis are reaching the end of their normal life expectancy, interest is high in repairing and refurbishing these future classics.
Like all high-volume mass-produced V8 engines, the Hemi has its inevitable share of issues. As a self-professed Mopar fan, this author has owned four vehicles with third-generation Hemi V8s, and the MDS-equipped 5.7 Hemi unit in question was from a 2011 Dodge Challenger R/T with a five-speed NAG1 automatic. In a previous story, we detailed the original cause of trouble on this MDS-equipped unit—a defect in the timing chain and chain guide/tensioner—and the Hemi’s subsequent failure at 235,000 miles from an issue related to improper dealership repairs.
If Your Dodge Dealership is Repairing Your 5.7 Hemi Engine in Conditions Like This, It’s Too Late to Run Away
(1) The backstory to this 5.7 Hemi begins at 66,000 miles (2014), when the timing chain unexpectedly snapped at highway speed in “Eco” mode during four-cylinder operation. The defect was repaired at a Dodge dealership in Moreno Valley, California, under Customer Satisfaction Notification P01. At the time, many dealerships were back-logged with Hemi timing chain defect repairs and this dealership took one or more poorly-advised shortcuts which we’ll talk about in a moment. These shortcuts eventually resulted in a failure of head gasket integrity around 235,000 miles, a testament to the forgiving design of the Hemi, but because the car is the author’s wife’s daily driver and not a weekend toy, it eventually forced the replacement of the engine with a new factory-fresh partial long-block.
Is a 5.7 Hemi Worth Rebuilding
(2) The dealer-repaired Hemi finally came out at 235,000 miles and was replaced with a new partial long-block unit from Mopar. Items like the intake manifold, oil pan, timing cover, and valve covers were reused.
After disassembling and inspecting the high-mileage Hemi at IMM Engines in Indio, California, we realized that the Hemi looked remarkably good inside and could be refurbished to near-new condition with most of its
