Odd Vibrations

[Memcdowe]

Hey,

Thanks in advance for any input. I have a 2020 JLUR 2.0 that I have now out about 35k miles on. Been a fantastic Jeep and have loved that little 2.0! I put a Metalcloak 3.5” Gamechanger lift on at 300 miles and swapped over my 37’s that I had on my JKU.

About 2-3 weeks ago I started noticing some harmonic / oscillating / pulsing vines going 65mph or so. Thoughts go straight to driveline vibes. FAD has front DS (Adam’s DS) not spinning and the rear is fine with no weights missing etc.

So, I start looking for culprits. Couldn’t find anything that would (or should) cause the vibes but I did have a worn drag link rod end so went ahead and upgraded that to an RPM Steering setup. I also switched tires from 37” Baja Boss MT’s to 38” Ridge Grapplers. None of these changes changed the vibrations.

I DID notice something peculiar today, though. When coasting or driving slowly etc I can give it just a tad of pedal….enough to engage turbo but RPM’s haven’t risen yet if that makes sense…..and I feel the vibration in the steering wheel. It feels like something is unbalanced and the engine when it’s at higher rpm makes it less noticeable etc.

So, what say you? Our local dealership is not an option. Would have to drive over an hour to
Take it to a decent service department for
Warranty work or diagnosis.

it feels like the turbo is vibrating (??‍) or ???

Again:
Driveline vibes filled out. Not DS.
Tires ruled out.

I do have a replacement tie rod to install as well. As I’m guessing the ends on it are going like the drag links did. I plan on checking torque on all of the motor mounts and transmission mounts etc. it’s had regular maintenance but it’s also been off-roaded a decent amount as a good rubicon should ? and has been turning heavy tires since I got it home. Ball joints are also stock. But not sure how that would cause the vibrations in feeling either.

The old rules I’ve played by with CJ’s and TJ’s don’t seem to be applying as well to these JL hahaha. Thanks for the advice in advance

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[GATORB8]

The turbo is so light and spins so fast, I can't imagine that's your issue.

I think concentrating on the parts that impact steering is probably your best bet.

Some ideas:

1. Tires/Wheels: Any chance they're still out of balance? Road Force balancing is an option if you haven't done that yet. If your wheel hub bore is larger than the hub you could try centering rings in case you aren't perfectly aligned (wheel to hub).

2. Tie Rod/Drag Link: Sounds like you have/are addressing this.

3. Track bar: Be worth checking bolt torque, bushings, and that the mounts are still solid.

4. Steering box: be worth checking that the mount is still solid.

 

[garykk]

Have you turned off the engine while rolling at 65 mph? That would eliminate the engine. How are the angles of the driveshafts? I would still be suspicious of the tires.

 

[Left Field]

I never eliminate driveshafts and tires from a vibration problem, even after they have been proven to not be the problem

I've noticed, but haven't tried yet, some of the vibration analyzer apps for phones. If they work they could be a useful tool to identify the guilty rotating part based on its rotating speed (RPM/60 = Hertz)

Based on your description I'm suspect of something related to the driveline - engine mounts, trans mount, driveshaft joint wear. Loading & unloading this path, like your turbo spool up example, can often show changes in vibration.

LF

 

[garykk]

I had a vibration on an older wrangler, turned out to be a bad trans mount.
A bad motor mount can cause a vibration as well.

 

[Memcdowe]

New drag link did not correct.
Trac bar inspected and torqued.
I’ll be checking all of the transmission and motor mounts tomorrow. The dealership replaced my steering box via the service bulletin. So I wouldn’t be surprised one but if they didn’t tighten properly.
And I know exactly what ya mean by never ruling out tires and driveshafts! Haha.

itnisnt vibrating even a little while coasting. ONLY when I give it a little gas. The vibrations are definitely harmonic. (Well, all are really, but this is definitely a pulsing vibe.)

 

[Memcdowe]

Ok, update.

Going 60-80 this is how it is acting: If my foot isn’t depressing the gas pedal, there are zero vibrations. None. But when I touch the pedaleveb The slightest but. Not even enough to change rpm guage and the vibration shows up. Harmonic. (Pulsing, oscillating, etc etc) when I give it more gas it will get a bit worse, turning this a constant dictation as well as a harmonic vibration.

36,088 miles 2020

Front driveshaft isn’t sping due to FAD. Replaced drag king. Checked tie rod (it was fine)

I’ve changed tires since it started to very different tires. Didn’t change it at all.

Rear driveshaft is spinning slll the time. Not just when I touch the gas pedal. Vibration is nonexistent unless I’m touching the pedal.

It feels like some motor mounts may be loose? Going to check them and transmission mounts.

 

[Jbish1977]

Ok, update.

Going 60-80 this is how it is acting: If my foot isn’t depressing the gas pedal, there are zero vibrations. None. But when I touch the pedaleveb The slightest but. Not even enough to change rpm guage and the vibration shows up. Harmonic. (Pulsing, oscillating, etc etc) when I give it more gas it will get a bit worse, turning this a constant dictation as well as a harmonic vibration.

36,088 miles 2020

Front driveshaft isn’t sping due to FAD. Replaced drag king. Checked tie rod (it was fine)

I’ve changed tires since it started to very different tires. Didn’t change it at all.

Rear driveshaft is spinning slll the time. Not just when I touch the gas pedal. Vibration is nonexistent unless I’m touching the pedal.

It feels like some motor mounts may be loose? Going to check them and transmission mounts.

Did you ever find a solution to your vibration issue?

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