• Welcome to the new NAXJA Forum! If your password does not work, please use "Forgot your password?" link on the log-in page. Please feel free to reach out to [email protected] if we can provide any assistance.

Yes, a vibration thread. I have vibes at speed.

H

HeavyMetal

NAXJA Forum User
Location
Fairfield, CT
So to cover a few things

Yes i have an SYE w/CV shaft
Yes i have been vibration free for a long time previous
No this isnt driveshaft related, or ujoint related, or exhaust related.
Also not steering or tire balance related :) (all these have been checked on)
i'm on an RE 4.5 w/33s D30/D44 combo
nothing has been changed or added to the jeep in the meantime since vibes began, so it has to be some part on its way out or out of whack

i took it for a 'spirited' highway ride and found the following:
-Its only harsh when im on the gas
-its only above 30-35
-its not really felt in the steering wheel or seat specifically at all until higher speed when it spreads
-its DEFINITELY front-end related.
-faster i go (65+) it gets intense
-my dash i can hear vibrating and as speed increases it spreads rearward and gets worse and worse with speed increase
-i can almost be sure i hear an almost faint 'pulsating' with the vibes that is in relation to tire spin speed when im off the gas and coasting

just for clarifications sake, this is not a wobble or any effect on handling,
its a harsh vibration - similar to when the front driveshaft ujoints are toast

its been suggested this may be wheel bearings? perhaps something else? just lookin for some more educated opinions before i go rip 'er apart in the cold. thanks guys
 
Last edited:
Busted tire belt?
 
If you jack up the front of the jeep and grab the wheel, you can check for play, that might help be an indicator of bearings. If the bearings were shot, and you had play, it could give you death wobble.

Of course, I have to mention this as well :)
http://www.jeepsunlimited.com/forums/showthread.php?t=707923

Entire list of everything that can cause death wobble:
-Front tires out of balance
-Front alignment out of spec
-Loose track bar
-Worn track bar bushings
-Worn track bar end
-Need adjustable track bar
-Bad bushings/joints in control arms
-Worn/damaged steering stabilizer
-Worn/damaged shocks
-Worn/damaged tie rod end
-Bad U Joint
-Bad ball joint
-Loose frame mount
-Steering box looseness
-Need drop pitman arm
-Driveshaft(s) not balanced
-Bad front hub assembly
Click to expand...
 
just for clarifications sake, this is not a wobble or any effect on handling

its a harsh vibration

(threw this in the main post as well now)

would slight play side to side (outside to inside) equal a wheel bearing? the balljoints appear to be solid
 
In my experience when I had a bad bearing I had movement side to side as well as if I pushed on the top or bottom of the wheel or pulled, like in/out movement. Generally mine was loose and it was pretty clear.
 
Further troubleshooting, you could start eliminating moving parts from the equation. Do you have locking hubs or do you still have that vaccum deal? Take off the front driveshaft if you do, maybe the driveshaft is bent (bad front dshaft ujoint?) and turning at a high speed is making it shake the whole Jeep?

Still bad if you're in neutral?

I dunno just throwing stuff out there.
 
Could be a worn out front driveshaft (particularly at the slip joint). thats stupidly common, easy to test by removing it.

Could be unit bearings on their way out. If you replace them, buy Timken ones (they are more expensive), or you'll be buying them again in 15k miles.

Could be balljoints

Could be a tire out of balance, out of round, or a bent wheel - rotate front to rear.
 
HeavyMetal said:
So to cover a few things

Yes i have an SYE w/CV shaft
Yes i have been vibration free for a long time previous
No this isnt driveshaft related, or ujoint related, or exhaust related.
Also not steering or tire balance related :) (all these have been checked on)
i'm on an RE 4.5 w/33s D30/D44 combo
nothing has been changed or added to the jeep in the meantime since vibes began, so it has to be some part on its way out or out of whack

i took it for a 'spirited' highway ride and found the following:
-Its only harsh when im on the gas
-its only above 30-35
-its not really felt in the steering wheel or seat specifically at all until higher speed when it spreads
-its DEFINITELY front-end related.
-faster i go (65+) it gets intense
-my dash i can hear vibrating and as speed increases it spreads rearward and gets worse and worse with speed increase
-i can almost be sure i hear an almost faint 'pulsating' with the vibes that is in relation to tire spin speed when im off the gas and coasting

just for clarifications sake, this is not a wobble or any effect on handling,
its a harsh vibration - similar to when the front driveshaft ujoints are toast

its been suggested this may be wheel bearings? perhaps something else? just lookin for some more educated opinions before i go rip 'er apart in the cold. thanks guys
Click to expand...
 
HeavyMetal said:
i have previously removed the front driveshaft and the problem persisted unfortunatly

no vaccuum disco, its a non-disco 97+ HP30
Click to expand...

And it still felt like front end... hrm well there's not a whole lot of moving stuff up there that it could be. Moving since you've already eliminated it from being a castor/camber/alignment thing.

Got a different set of wheels you can throw on it?
 
thread have ur tires been balance to 100 miles pr. hour and are tires wearing evenly . check for missing tire or rubber lugs.wheel balanceing should be done on a rotating balancer.Not a static balancer.sincercly tony
 
yes the tires have been balanced as stated in original post. on the rotating machine.

the wheels are OEM aluminum or whatever theyre constructed out of so i do not believe theyre bent.

so i may assume this is unit bearings shenanigans, which i guess i should do a search on
 
You stated the vibration is somewhat cyclical in nature. You also stated it's not the tires or driveshafts. Unfortunately I suspect the second statement isn't true- I wonder about the CV part of the rear driveshaft. Tires and wheel bearings don't change their tune depending on throttle. The rear driveshaft and rear gears do, however. I'd be looking close at the rear driveline.
 
well the rear driveshaft is a 1 year old tom woods CV shaft and everything on it is in pretty tip top shape as far as i can tell. the vibration itself isnt so much cyclical, as is the faint sound i hear behind it
 
speaking of a cyclical sound, i had some of that when the front axle pinion angle was off by a bunch (after messing around with control arm lengths). kind of a cyclical droning noise that got louder and louder as speed went higher. if your pinion angle seems to be good, then please disregard the last 2 sentences.

also, when i recently had my wheels/tires balanced at Firestone, i noticed some wobbling from the rear and 2 weeks later i noticed that the rear-passenger wheel didn't have any balancing weights on it. i went back to Firestone and they told me that this particular wheel couldn't be balanced because the tire surface knobs were too unleveled (that was their excuse, i still need check on this). so, for 2 weeks i had no idea and was driving with 1 unbalanced wheel, all because Firestone forgot to tell me. i'm sure yours are well balances as you noted, but just wanted to bring up a possibility.
 
That's a good price if you're just looking to hang parts on the thing, but it won't fix your issue. Have you actually checked the rear driveshaft for play? It's a real simple check provided there's no load on the shaft.
 
yes both driveshafts have been looked over extensively and the front one removed and they show no issues, rear driveshaft is basically new and rock solid.

why do you assume me replacing my hub/wheel bearings will not solve the issue if thats what it could very well be?

there is a little bit of play back and forth in the driverside wheel when jacked up, and the jeep has around 125k on it
 
Last edited:
Do you know anything about vehicle vibrations?

What you're describing is not a wheel, tire, or axle shaft vibration. If your description is incorrect, then it could be from a wheel bearing. Hold the keyboard a little closer to the vehicle, please.

In a nutshell anything wheel speed related (oversimplified) comes down to a thump, where driveline is a buzz. Wheel and tire (and bearing) will shake the steering wheel, or perceptibly bounce the seat. Rear end and driveline, due to the attendant higher frequencies, are more likely to vibrate all the change in a cupholder around. Cyclic is the biggest clue, wheel and tire issues do not have the capability to generate an audible cyclic vibration.

No offense, but all you need to do is find someone who knows this stuff and take them for a 5 mile spin and you won't be wasting money on unneeded parts. You could also go to a dealership that has a Vetronix or similar vibration analyzer and send me the Hz, g/sec, and 1/2/3/4 order data. Your call.
 
JJacobs said:
Hold the keyboard a little closer to the vehicle, please.
Click to expand...
i dont know what you mean by this, and i hope it isnt what i think it means. (web wheeler?)

if its the rear, i dont understand what it is then if all ujoints are top notch, the driveshaft is tip top, and the tires are balanced.

i have some play in the front wheel side to side (not a LOT), so i dont think me replacing the hub assembly is really that far off-base of an idea (especially considering it has so many miles on it and was worked on a month ago or so,i may have under or overtorqued it, did a ujoint replacement), its hard to really describe spot-on a feeling of vibration on the internet so who knows how my description can be construed otherwise.

The vibration does not goes cyclically, and i never claimed it to, its just a background faint noise behind the constant straight vibration. the vibe only is harsh on acceleration, and i only hear the faint cyclical sound on coast, but the vibration itself is a constant thing.
 
Last edited:
You must log in or register to reply here.

Similar threads

H
95 XJ Pulsing Vibration At Highway Speed
Replies
13
Views
4K
RCP Phx
R
U
Drive Line Vibration Driving Me Crazy
2
Replies
22
Views
6K
RCP Phx
R
8
Intermittent vibration in rear
Replies
9
Views
1K
89XJClay
8
P
2K IDLE - Odd Shifting - TPS? (I know.. I know)
Replies
3
Views
2K
Unclewolverine
U
T
Obnoxious driveline noise
Replies
5
Views
2K
Da XJ nut
D
Back
Top