Shake while cruising on highway

[Nick B]

My 2000 Wrangler drives fine on the highway up until ~65mph. At this speed and beyond, the Jeep will shake/vibrate most of the time but not every time. It is not a violent shake but it is worrisome when I go to pass someone and the whole Jeep shakes. The alignment is recent and good and none of the bushings are worn. The steering box, pitman arm, power steering pump, and steering stabilizer are newer and there is relatively no slop in the steering wheel.

I also have 31 inch Goodyear Wranglers that I run about 32psi (the recommended psi printed on the label in the door jam) and I do not have a lift yet.

Will decreasing the tire psi stop the shake? I know lowering it can lead to a less rough ride, but would it also fix the problem?

 

[Dcook65]

Had the tires balanced?

 

[bromel]

Get the tires rebalanced, and insist the shop get them to zero. And bring down the PSI to 28.

 

[Nick B]

Had the tires balanced?

Tires were replaced and balanced about 25,000 miles ago. Still have good tread and wheel weights don't appear to have moved out of place.

 

[Nick B]

Get the tires rebalanced, and insist the shop get them to zero. And bring down the PSI to 28.

I'll lower the pressure and test it out. If the shake is still there then I'll get them re balanced. Doing some rust repair at the moment so it won't be tested for another day or two.

 

[Jerry Bransford]

Tires were replaced and balanced about 25,000 miles ago. Still have good tread and wheel weights don't appear to have moved out of place.

Doesn't matter, get them balanced again. And not all shops are willing to spend the time to get tires balanced perfectly which is important on a vehicle with a solid front-axle like the TJ and many trucks have... and the bigger the tire, the more important balance becomes.

Keep in mind that with 25k miles on those tires they have not worn perfectly so it's pretty much assured that speed sensitive vibration you're experiencing is tire related.

 

[Goatman]

Definitely try dropping tire pressure down. Drop in 2 psi intervals until you find the best pressure for you. It will probably be in the 26-28 range. Rotate them front to rear too. That might help any off wear pattern from the front axle, though the rears will probably be picking up the same pattern from higher psi. If that doesn't help then off to the tire balance machine.

 

[Mjv]

Wheel weights can come off. I had some tires balanced and the weight came off on the way home. X2, check balance.

 

[AndyG]

If it isn't your tires... Which need to be checked before anything... Check out your drive shaft or pull the front drive shaft and see what happens.

What can be deceptive is a tire can appear to be fine and actually even balance pretty good but have issues... deteriorating belts, etc. ... especially if it's been sitting.

You have a fixable problem.

 

[Nick B]

Rotated my tires and the problem is basically gone. Got the Jeep up to 75mph and there was no vibration from the front tires, but a very small amount from the rear. But when I am cruising between 60-70mph on the highway there is no vibration at all.
Thanks for all the suggestions

 

[AndyG]

Everyone that has death wobble needs to start with simply rotating the tires.

 

[Raymund]

A few weeks late here but my driver's side (yes those weird TJs with the steering wheel on the other side ) started to get a tad funky with similar symptoms.

Rotated and all good.

 

[AndyG]

A few weeks late here but my driver's side (yes those weird TJs with the steering wheel on the other side ) started to get a tad funky with similar symptoms.

Rotated and all good.

Australian- he rotated the steering wheel.

 

[Raymund]

I only get death wobble when I reverse. Weird. Still trying to figure it out...

 

[Goatman]

Same reason you flush the toilet and the water spins the wrong direction (luckily still down, tho.)

 

[Raymund]

Just to add something randomly related, I'm mostly left handed so the stick works well for me here. I'd find it weird shifting with my non-dominant right hand.

I'm hoping this doesn't leave me open to other jokes now but hey, I'm bored so...

 

[Goatman]

I've watched the BBC's 'Top Gear' and they seam to seamlessly switch between left-hand and wrong-hand steering. All the while dri8the snot out of the vehicles and shifting perfectly the whole time. Hell, when I screwed up my elbow years ago I couldn't even swap sides and wipe my !