Shaking at high speeds

[01jeepgc]

I have a 2001 Jeep Grand Cherokee, I-6. Last week while on the highway once I hit roughly 82 miles per hours the vehicle began to shake pretty bad. I suspect it is frong end related because there is some looseness in the front end causing it to pull to the right and also pull if I hit a rutt.

Any ideas that may help me more isolate the problem and, better yet, the solution needed.

Thanks.

 

[SteelHeadz]

Wobbles, vibrations are usually caused and or intensified by a worn or loose component. Tire's varies on their speed ratings and even at that, depends on the size and application. If you have any loose or worn steering and suspension components, i would address those issues first then re-evaluate the shake issue. Front end alignment plays a role in this as well so after you have checked and replaced the worn components, checked the wheel balance then have the front end alignment checked.

 

[firestarter]

Sounds like signs of "Death wobble". Do a thread search on the forum and you'll find quite a lot of info since it's a pretty common issue with the XJ. I just went through it all and it turned out to be bad tires for me but then again it's usually different for everyone.

 

[01jeepgc]

Yep, found the thread on death wobble. Will begin with checking components and going from there. Thanks for the advise, these threads are wonderful.

This is going to be my daughters car and I want to be as confident as possible that this wont happen to her while cruising down the highway.

This is fixable, correct?

 

[firestarter]

Very fixable. But I know the feeling, it literally seems like the front-end is gonna come right off the vehicle, quite scary if you're not expecting it I spent about a good 3 weeks reading up on it and replacing a few things here and there but it really came down to getting new tires. Granted, my tires were really really worn down but I don't think the design should be this susceptible to such a minor imperfection.

This link lead me to believe that it could be the tires and sure enough it resolved the issue 100%
Yucca-Man: Death Wobble

But in reading around forums you'll hear people replacing *all* sorts of suspension components to fix this. Initially i stopped by a firestone and asked them if they've ever fixed in and they guy told me that they usually replace the entire front-end instead of troubleshooting each part .... talk about overkill!

 

[mud4feet]

OK...let me get this straight. This will be your daughter's car and this problem occurs at 82 mph? So, I'm assuming you want your daughter to be able to excede 82 mph in a Jeep and be vibration-free. Trust me, it's not the "death wobble" that you have read about.....that phenomena occurs at a much lower speed....and you will definitely know when that occurs. Sounds like a tire problem to me.....and best of luck to your daughter.

 

[01jeepgc]

Mud4feet,

Yeah, thats what I said. Read my post again. It happened to me, and yes it was at 82 miles per hour. Thats not a far stretch when highway mph is 75. All the road work going on during the summers and the "uneven lane's" due to re-surfacing.

In the post I have read it seems to happen at a pretty wide range of mph and that is exactly why I am on here trying to get it fixed.

If I were you I wouldn't assume anything because you are most definitely wrong?

 

[Bounty__Hunter]

If the wobble is induced by speed only and not by a bump, then it's likely a tire balance issue. Then you've got worn parts up front that allow that tire vibration to escalate into a wobble. I'd inspect the steering and trackbar closely while somebody turns the steering, preferably bouncing the steering off of full lock in order to determine what's loose/worn.

 

[firestarter]

Out of curiosity have you noticed mpg dropping to an all time low when going above 80? I tried it once (something must be out on my jeep) and my mileage went to practically nothing ... could see the gauge moving at a steady rate

So I've never went above 75 for the past couple years.

 

[01jeepgc]

There was bump involved. The uneven lane change where the new asphalt was three inches higher than than the other lane.

I will probably start with new tires since I am going to need them anyway. Then I will take to my mechanic to check out the suspension, steering and other front end components.

 

[MudderChuck]

Just for the heck of it, check the front U Joints. Had one XJ that picked up a vibration right around 80 MPH. Most of the vibration was the U-joint and a couple marginal tie rod ends seemed to magnify the vibrations. almost to the point of shimmy.
The way I check front U-Joints is to jack the tire off the ground, jam something in the yoke (long socket extension) and rotate the tire using a slow moderate pressure and kind of bounce the weight of the tire off of the socket extension. I look right at the rubber seal at the U-Joint cap (flashlight), thats usually where I first see the play, with worn U-joints.
Not a fast rule, but I tend to look at tire balance when the vibration is around 60 MPH and tend to look at the drive train at higher speeds. Had one front drive shaft, with worn slip splines, that would wobble/vibrate at around 75 MPH.

 

[mud4feet]

Mud4feet,

Yeah, thats what I said. Read my post again. It happened to me, and yes it was at 82 miles per hour. Thats not a far stretch when highway mph is 75. All the road work going on during the summers and the "uneven lane's" due to re-surfacing.

In the post I have read it seems to happen at a pretty wide range of mph and that is exactly why I am on here trying to get it fixed.

If I were you I wouldn't assume anything because you are most definitely wrong?

Please forgive me....I drive a 4-banger Wrangler so she never sees 80 mph and I'm fine with that. And, yes, I know what it means when you "assume" things....my bad. I've had the "death wobble" and if I was doin' 80+, I'd be dead - it's that bad!! Anyway, sorry to be a smart arse when you're just trying to get a problem fixed. Most of my "wobbling" issues have been tire related. I'll stick to the Wrangler forum and try to keep my "*******ness" in check. Welcome to the "Z"......you've come to the right place. And, again, best of luck.

sometimes I drink too much,
mud

 

[01jeepgc]

No worries, mud4feet! Just trying to get it fixed. I am going to get some new tires on it first and then if it shows up again I will begin checking other things out. I definitely know the value of these forums, I have been a member of the Chrysler 300 forum for years and it has saved me lots of money.

Thanks for all the advice everyone!

 

[01jeepgc]

Put new tires on the Jeep and took to my mechanic. He found some looseness with the drag links and said that could definitely create some shaking when on uneven ground. Ok'd those to be replaced.

We'll see how that affects the drive of the vehicle on uneven ground.

 

[superj]

the drag link? isn't that only for centering your steering wheel?

 

[01jeepgc]

the drag link? isn't that only for centering your steering wheel?

Not from what I understand. In fact from what I have read, when warn they can negatively affect the handling and stability while driving at speed. Especially in a lifted vehicle. Google it and you will see it is involved in much more than "centering your steering wheel".

 

[superj]

stupid work computers make it a pain to post on the forums.

i had a long paragraph about my experience concerning drag links since my other post but the work computer deleted it. needless to say, i now know the whole center assembly from tie rod end to tie rod end is called the drag link