Vibration Problem

[wtxbadger]

I have not posted here in the past, but have enjoyed reading everyones posts and learning from your experiences.

I have a 2006 Unlimited that has started shuddering when it is driven for a while. I can't give you a first hand account as the problem just started a couple of days ago with my wife driving it. She says that after she has been driving for a while the Jeep starts shuddering from front to back almost like the brakes are pulsing as she drives down the road. It does not matter what speed the Jeep is going or what gear it is in, it just starts with this problem. She says the engine seems to be running fine and not running rough or missing.

I plan on driving it tomorrow and trying to duplicate the problem, but wanted to see if anyone here has ever had a similar problem or has an idea of what to check.


Thanks

wtxbadger

 

[SteelHeadz]

Gather as much symptoms as possible when you drive it then let us know so we can try to figure this out.

 

[xt master]

Do you have a lift?

 

[wtxbadger]

It is completely stock with no lift. My wife said that the problem starts after she has been driving for 30 to 40 minutes. When she first told me about this I thought it might be a tire separating, but she described it as a back and forth motion and not a shimmy or wobble. Plan on taking it out later today and seeing if I can make it happen again. She says it almost like the brakes are pulsing on and off.

 

[wtxbadger]

Well I drove it around in town and on the highway for over an hour and still don't have much to go on. For about a half mile on the highway I did feel a vibration and then it quit. No unusual noises from the drivetrain at all. The only thing I did notice is that the brakes don't feel quite right when stopping. They feel like they are pulsing when braking. This does not happen at every stop, but it did happen on several stops.

It kind of reminds me of a 96 chevy 4X4 I had that when the ABS kicked in the pedal would pulse.

The engine runs fine, not missing or running rough and runs out normally. A visual inspection of drive train, tires, and undercarriage don't reveal anything unusual.

Any ideas on what else to check out?

Thanks


wtxbadger

 

[SteelHeadz]

A pulsation on the brake pedal when applying brakes on a light or hard stop (not a panic stop) , generally indicates a warped rotor. This is also sometimes felt on the steering wheel with a rotational wobble. If the vibration is evident ONLY when the breaks are applied, i would rule the cause towards a warped rotor. IF the vibration is only present at certain speeds , it's possible that the wheel balance is off and have the tires checked as well for an out of round due to a belt separation. In this scenario, usually you would have a low speed wobble/ vibration at a low frequency. Higher frequency vibrations are usually caused by an out of balanced driveline or wheels. Wheel Vibrations usually occurs somewhere between 35- 45mph then smooths out after and restarts at around 70-75mph. The speed variation inbetween varies on how bad the out of balance component is, thus, the cancelling varies in between. Does any of this make any sense on the conditions your experiencing?

 

[wtxbadger]

Makes sense and we are both thinking along the same lines. That being said I thought about a warped rotor, but if a rotor is warped the problem should repeat pretty much every time I stop.

The vibration seems to be intermittent, occurs at various speeds and road conditions/surfaces. That last statement is made based solely on what my wife related to me.

When I did feel a vibration this morning for about a half mile I did not feel anything in the way of feedback in the steering wheel. Just felt like the entire vehicle was vibrating. I was going about 65 mph when it started. Based on my wifes account I maintained my speed expecting the vibration to get worse as it has done for her, but no dice it just faded away.

I fully expected to drive it and pinpoint the problem fairly quick. Just aggravates the you know what out of me when I can't figure out something like this.

Thanks for the leads on what to check. Thinking the next thing to do is pull the wheels and inspect the rotors for warpage, sticking caliper, and maybe have the tires balanced again.

 

[SteelHeadz]

Depending on the severity of how warped the rotors are, would be contingent on what speed it would be evident during brake applications. Sometimes over 35mph , sometimes over 70mph on a light brake application.

 

[xt master]

Could still be a rotor problem.By any chance does your wife drive with booth feet,and is it an automatic.If she does maybe she is lightly pushing on the brakes while driving and over heating the rotor.

 

[wtxbadger]

It is a manual transmission. That is an interesting idea on the rotors overheating. She tends to hard braking when coming to a stop. Scares the crud out of me when I am the passenger, which does not happen very often. Did not get a chance to yank the wheels and do a visual on the rotors and pads. Maybe tomorrow, work keeps getting in the way of every thing else.

 

[Crazy4diesels]

Check your emergency brake cables and make sure they are not sticking. Often if the e-brake is dragging you'll get shudder once it heats up. One side might be the culprit or you might find the center cable sticking. Best of luck - John

 

[jfrabat]

Have you gone wheeling lately? My front DS took a hit once, and it caused something similar to what you are describing. When I checked it, it turned out to be slightly bent (I have alloy shafts, so no vacuum disco on my front shaft as there is ussually on a YJ).

 

[wtxbadger]

Have not had a chance to get offroad for several months now. Hoping to get a chance tomorrow to geta a better look at the ebrake cables, rotors, and other possible causes.

Will let you know if I find anything. Appreciate all of the suggestions on things to check.

 

[Sine Deviance]

It is a manual transmission. That is an interesting idea on the rotors overheating. She tends to hard braking when coming to a stop. Scares the crud out of me when I am the passenger, which does not happen very often.

Yeah, my mom does that too. I'm used to braking early from driving Jeeps, but she is used to a little '01 Eclipse GT Spyder which stops on a dime. She came about six inches from running us into someone's rear-end the first day I had my YJ. After that I don't let her drive it anymore

Routine hard stops will cause the rotors/pads to wear faster and you might get some brake fade, but it shouldn't ever cause overheating unless you're constantly under hard braking, i.e. on a race course or a very curvy, very hilly mountain road. If one of the rotors is overheating you probably have a stuck caliper, but if that was the case you'd likely have some brake drag pulling you to the left or to the right on the highway. If both or all four are overheating I'd guess it'd be a sticking booster, pedal, or master cylinder, but that is extremely uncommon in something as new as '06.

Warped rotors is still a good possibility. But I don't see how they'd cause that vibration when you're just cruising unless the brakes are stuck a little.

 

[wtxbadger]

Thanks for all of the great feedback. The warped brake rotor and sticking caliper was the problem. Finally had some time to drive it long enough to figure it out, but never had the chance to post what the problem was. Work kept getting in the way.

Plan on replacing the rotors with heavier duty aftermarket ones and replacing the sticking caliper.

wtxbadger