As the owner of numerous solid front axle-equipped automobiles, I’ve dealt with the violent shake that is “Death Wobble” a number of times. And yet even I would soil my favorite set of cargo shorts were I piloting this white Jeep Grand Cherokee. Because it appears that there’s a massive earthquake affecting only its front axle and not the world around it, and that’s horrifying.
I stumbled across this video on my Facebook feed, which is constantly filled with far too many off-road-related postings and far too few kitten photos (everyone needs at least one kitten photo a day).
Tijuana, Baja California-based off-road club Malcriados Offroad uploaded the video with the caption (translated from Spanish): “For those who don’t know him here’s the wobble — of death 💀💀.”
I’ve not only experienced violent death wobble before, thanks to a 1996 Jeep Cherokee with worn-out steering parts and a 1948 Willys CJ-2A with bad kingpin bearings, but I’ve even written multiple articles on it, including one featuring a video of a JK Wrangler doing the death wobble dance. But that JK’s troubles, shown below, seem relatively tame compared to this ZJ Grand Cherokee’s.
The video begins with someone saying “Blowout,” followed by a different person saying “Oh shit. Damn! Those are some bad speed wobbles” as the two people in the car drive by a 1996-1998 (post-mid-cycle refresh) first-generation Jeep Grand Cherokee with a major front axle problem.
This appears to be a classic case of death wobble, usually caused by worn out steering and suspension parts (oftentimes a bad track bar), as I wrote in my previous story. From that article:
The problem with death wobble is that it’s not always easy to fix. Though it’s usually caused by a worn out track bar or track bar bracket, bad tie rod ends, crusty control arm bushings, wrecked ball joints, sloppy steering boxes, and even bad tire alignment can all contribute to the horrible shake.
Sometimes people temper death wobble with a bigger steering damper (basically like a shock for your steering; you can see one in the image below)—it’s a solution that works, but it’s considered by most just a way of masking the play that exists somewhere in the steering or suspension.
The result of these worn parts is that when hitting a bump—especially while turning—the front axle begins to shake and the vehicle vigorously bucks up and down. The whole thing is usually loud and scary, and it feels like the entire machine is about to fall apart. It’s no wonder that, recently, after customers experienced the chaotic issue in their new Wranglers, they sued FCA.
Then FCA announced that it had a fix to the issue that chief technical compliance officer Mark Chernoby describes in a Detroit Free Press story, saying:
The issue is resonance, he said, describing it as equivalent to hitting a tuning fork.
“if you bang it with that frequency it’ll just sit there and keep going forever. It won’t slow down, it won’t dissipate, and that’s essentially what we’re talking about here with the vibration in the new Wrangler,” Chernoby said. “When you hit a bump in the road, if everything is just right, this suspension can set off that resonance and what we started seeing is as soon as it got cold this past fall, early winter, we started seeing complaints.”
The issue, Chernoby said, had to do with air getting into the damper on the front suspension of the Wrangler during cold temperatures, when oil becomes “thick like molasses” and air bubbles take a long time to get out of the oil.
“We were losing the damping on some of these parts,” he said, noting that the part is supposed to quickly damp out the resonance when it develops.
It’s a fascinating problem that’s been plaguing Jeeps since 1941, and holy crap, is it a spectacle to see in action on the highway. From behind the wheel, though, it’s truly dreadful, and I’m still seeing a professional about my experience with my ’48 Willys.
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