Chevy V8 failures have been a topic of significant discussion lately. Earlier this year, we highlighted a video documenting the teardown of a junked 6.2-liter GM L87 V8 that was removed from a new Cadillac Escalade with single-digit mileage. Sure, a low-mileage engine that has failed suddenly usually makes for an interesting visual, but in that case, the autopsy ended up being inconclusive. That was before the V8 situation really blew up (sorry); now GM has an official recall on its hands. With the elevated scrutiny, it was only a matter of time before some seasoned motors received more careful attention. Sure enough, YouTube mechanic Eric (I Do Cars) just got his hands on one, and the carnage is pretty spectacular.
While the video is nearly an hour long, the teardown itself only takes about 35 minutes of runtime. Before digging in, Eric takes note of a couple of things. For starters, this engine was in fact removed from a recalled GM SUV—a 2022 GMC Yukon Denali. Second, this engine has been opened up before, as evidenced by the discolored replacement oil pan. Third (and related), the engine can be cranked over by hand, indicating that none of the internal components are binding.
The whole thing starts uneventfully, with Eric noting that the oil residue inside the engine appears normal and that there are no obvious signs of debris—both good signs that he can salvage some parts off of this motor. The first sign of trouble comes from the pushrods, several of which show abnormal wear.
The next obvious sign of a problem presents when he removes the engine’s lifters. While none of the lifters have collapsed, all of them show indications of exposure to debris, and one of them has been chewed up pretty badly, with an entire chunk missing from its roller (a sign that the component itself is failing).
When the oil pan comes off, the extent of the problem becomes obvious. The maple syrup hue we saw elsewhere in the engine has been replaced here by almost a pure carbon-black. This sucker has been cooked, and badly enough that it’s likely what locked up the engine, which Eric notes is only spinning for him because somebody already loosened several of the bolts holding the crank assembly to the block.
Ever seen a small-block with all eight of its connecting rod bearings completely shot? Well, now you have. There’s also a nice chunk missing from one of the camshaft lobes, and signs of scoring on the front of the block from impact with the crankshaft. Despite the devastation, most of the teardown goes pretty smoothly.
Eric’s conclusion is that this particular recalled V8 failed more slowly than some owners have reported. Lack of lubrication would explain the buildup of excess heat, leading to the blackened oil varnish where components are attached to the crankshaft. He even theorizes that the driver may have been ignoring signs of engine degradation and/or early failure for a while before it gave up on them.
While he stops short of offering an exact cause of death in this particular instance, it’s clear that this V8 was subject to several of GM’s known trouble spots. The company’s recall notice suggested that its wear-related failures are most likely related to machining issues with the engine’s crankshaft and/or connecting rods—both of which were called out in this video.
Have you been inside one of GM’s recently recalled 6.2-liter V8s? Drop us a line at [email protected] if you’ve seen anything interesting!
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