If you drive a Jeep Cherokee or Grand Cherokee and are considering a suspension lift, you may want to think twice. Unfortunately, I was forced to learn this the hard way. I bought a brand new 2001 Jeep Cherokee a couple years ago, and almost immediately stacked on Pro Comp’s 3” lift kit with some 32 x 11.50 r 15 Super Swamper TSL tires. After a couple months of good riding, I started to experience what jeep enthusiasts have come to know as “the death wobble.”The death wobble is basically when you are driving your lifted jeep down the road and the front end starts to shake violently. It can happen at virtually any speed, though mostly above 40 mph or so, and is a frightening experience, especially for those witnessing it for the first time. Now it doesn’t throw you off the road or anything … the front end just shakes. And the only way to stop it is to slow down and pull over. So it wasn’t that hard to get used to at first. But as it happened more and more, it seemed to get more and more out of control.
After driving with at least one death wobble per day for about three months, I decided to take it into the shop and see what the problem was. Being of course that off-road shops are primarily in the business of ripping people off, they gave me a list of “everything that was wrong with the front end that is causing the ‘TJ shimmy.’” Their proposal included the rotation and balancing of my tires, new front (and rear “cause you might as well”) shocks, new and stronger track bar, new and stronger drop pitman arm, new and stronger lower control arms with some special urethane bushings, and new sway bar links. Basically, with the exception of my original lift springs, the reinstallation of the entire Pro Comp lift kit with “better” components.
The bill was just over $1000.00. But to fix my death wobble, and hence my daily fear for my life, it was worth it. And even better, the new components would be strong enough to support a 6” lift if I ever wanted to go that big. The words of the salesman still ring in my ears: “Dude, you could totally run 35s with this setup.”
For the next couple months, everything ran fine again and I just assumed that my former Pro Comp parts just sucked. I even took the kid’s advice and jumped up to 33 x 12.50 r 15 tires. My new components were working brilliantly. Then one day, riding down I-70 toward the mountains, I hit a pothole and back came the death wobble. For the next couple months, I experienced the death wobble every time I hit a pothole, crack, or even merged onto a simple uneven lane.
Back at the shop, the guys, obviously not recognizing me from six months before, gave me the same proposal as the first time … almost word for word, too. My shocks, track bar, pitman arm and control arms were all shot again and needed replaced with their “better and stronger components.” The guys didn’t even take the time to see if my components were the same ones they had sitting on the shelf. In fact, the parts they wanted to give me this time were likely the same Pro Comp components they had replaced initially. At this point, I realized that I’d have to take matters into my own hands.
I had a buddy sit in the driver’s seat of my jeep and shake the steering wheel back and forth in an attempt to recreate the death wobble so I could view it from the other side. After not even two minutes, it became clear to me what the problem was. All my components were fine. The shaking was coming from the frame rail, which is connected to the axle.
What was happening was simple: My tires, as off road tires tend to do, kept going out of balance. Therefore, when I hit a pothole or uneven pavement, or too high a road speed, the tires would start to wobble and fight back and forth against each other. This is probably how Fred Flintstone felt driving around with those rock tires. The fighting tires would cause the axle to shake back and forth, which in turn caused the frame rail to shake. Hence the death wobble. Now the wobble could have been stabilized by the bar attached to the frame rail; if only it was attached to a real frame.
See, Jeep Cherokees and Grand Cherokees have what is referred to as a unibody design. This means that they don’t have frames like a real vehicle, just a combination between a frame and a body. It’s kind of like a tin can on wheels. And if you put tires under that tin can that are too big and heavy for it to handle, it’s going to shake all over the road.
Now I’m not saying don’t lift your Cherokee, I’m just saying don’t lift your Cherokee too high. It can handle 31s or 32s, but if you get any bigger or heavier tires, it won’t be strong enough to consistently support them. If you want to lift a Jeep vehicle for off road purposes, I’d recommend a Wrangler. It has a frame, meaning it can handle big and heavy tires, not to mention a roll over.
If you’ve already got a Jeep Cherokee and are experiencing death wobble, don’t listen to the guys at the shop. They’re just trying to get your money! Test each of the components of your front end yourself. Most of them are rock solid and rarely need replacement. Instead, just get your tires balanced. It should fix the problem right away, at least until the tires go out of balance again. To end it permanently, unless you can somehow fabricate a stabilizer bar to strengthen the front-end frame rail, the only thing you can really do is switch down to smaller tires. Or buy a normal road car …
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