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jheat71

car is vibrating while accelerating ??? not tires

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my mechanic was ready to put in a new axle and then said i didn't need one ........ had another shop put the car on a lift and they checked the the drive train ............ so here are the symptoms the car will vibrate and only vibrate when you press the accelerator ( the vibrations or shaking is in the drviers seat area ) when going up hill the car will shake 10X as bad almost as if you're try to rock the car back and forwards .............. so next on my list is the u joint and trans bushing and maybe wheel bearing ( none of the wheels seems to show any issues no wobbling or signs of being out of balance

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Sounds like a frozen U-joint on the propeller shaft (ie main driveshaft down the center of the car).

 

I had a bad one on my 2001 with manual trans and it would shake like crazy when taking off from a stop.

 

I had it replaced with a used shaft for about $400.00

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my mechanic was ready to put in a new axle and then said i didn't need one ........ had another shop put the car on a lift and they checked the the drive train ............ so here are the symptoms the car will vibrate and only vibrate when you press the accelerator ( the vibrations or shaking is in the drviers seat area ) when going up hill the car will shake 10X as bad almost as if you're try to rock the car back and forwards .............. so next on my list is the u joint and trans bushing and maybe wheel bearing ( none of the wheels seems to show any issues no wobbling or signs of being out of balance
I understand you have to work with your mechanic, but there's nothing visual that you can see to tell if the DOJ is bad with these symptoms. The symptoms you describe are classic for a bad DOJ. Over the years I've had 4 or 5 of these among my cars. I've owned over 10 Subarus over the last 15 years and most of them were "retired" with 250K miles or more on them and I've never had a bad u joint or failed driveshaft. I'm just going with the statistics here. I still think it's the axle; just don't know which side.

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ok Ed sounds good what ur saying about the axle ............ is there away a mechanic can visually see if there is a problem ......... i gues what i'm saying is what does he need to look for to see if the axle is bad ........... thanks again for all the input everyone

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ok Ed sounds good what ur saying about the axle ............ is there away a mechanic can visually see if there is a problem ......... i gues what i'm saying is what does he need to look for to see if the axle is bad ........... thanks again for all the input everyone
I'm not a professional mechanic, but if I had a lift, I'd put the car in the air and have someone in the driver's seat put the car in gear and get it up to a reasonable speed to see if the vibration comes and goes with positive and trailing throttle and observe the axles and listen for noise that goes with the vibration.

 

The other alternative is to replace one axle at a time and see if the problem goes away. For all the time and effort you've spent on it so far this might be the easiest solution. In the event that doesn't solve the problem, you can always put the axles back on.

Edited by edrach

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Changing the front shafts from side to side can often eliminate vibrations. By swapping them over, the joints drive against the relatively unused (only used when reversing) thrust faces of the joints. I do this to my 99 Forester once a year, just to get longer life from them.

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Changing the front shafts from side to side can often eliminate vibrations. By swapping them over, the joints drive against the relatively unused (only used when reversing) thrust faces of the joints. I do this to my 99 Forester once a year, just to get longer life from them.
I've often thought of doing that; makes sense knowing how the DOJ wears out.

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no they get a ( humping ) the vibrations cycle with a rythem almost like a surge and whould be worse the hoter they get they only get thiss on inside cv the outer will just click and tear itself apart but the iner will vibrtae but only if dry i doubt that its a cv have seen som realy bad ones drive fine till they broke keep looking

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could a worn out DOJ cause the car to vibrate like an out of balance washer machine ?

 

Yes, this is exactly what mine did.

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REPLACE THE FRONT AXLES!!!!!

 

Don't look at them.

 

Replace them.

 

It takes 20 mins per side or less.

 

Axles are cheap, relativelty.

 

Don't let anybody tell you it's anything else.

 

Vibration under acceleration means the front axles are bad.

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could a worn out DOJ cause the car to vibrate like an out of balance washer machine ?
Yes. I had one axle that was so bad it felt like the transmission was about to fall out ofthe car. I've also had it so slight, that I knew it was there and my mechanic didn't believe it was a problem. I changed the axle myself and the vibration went away.

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REPLACE THE FRONT AXLES!!!!!

 

Don't look at them.

 

Replace them.

 

It takes 20 mins per side or less.

 

Axles are cheap, relativelty.

 

Don't let anybody tell you it's anything else.

 

Vibration under acceleration means the front axles are bad.

 

THIS!!!!! And don't use aftermarket ones or you will have the same issue. If its really bugging you, get original Subaru axles and be done with it.

 

I have a set of brand new aftermarket axles I pulled from a '05 Outback 2.5i that caused a nasty vibration. New set of OEM axles and no more vibration.

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sounds good .......... ok axles this week ................ strange thing though when i picked up the car from the mechanic he said he did find something wrong it was the rear transmission mounts were both broke , just wondering if this could also be part of the problem ? thanks again everyone when i take the car in tomorrow i will have the axles replaced as well as the transmission mounts

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There's only one transmission mount and it's pretty stout. Very flexible, but hard to break because of the way it's made. I'd be surprised if the mount was actually broken.

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jheat71, my car has similar symptoms. Vibrations while your foot is on the gas. My mechanic has traced it down to the bearing inside the transmission that supports the front axle stubs. See this link - http://www.subaruoutback.org/forums/66-problems-maintenance/23368-ring-clips-cv-joint-axle.html

 

Look at the forth post and the bearing is item 6 in the picture. I do not know that parts name. All I can say is that I have many of the symptoms you experience.

 

I will get the car back on Thursday and let you know for certain if replacing that bearing solved my problem.

 

Steve

Edited by Steves72

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my $ is on bad cv axles.

 

front axles cost 65 bucks a piece after the core charge is credited (meaning you bring the old axles to the parts store and turn them in when u get the new ones)

 

The only other thing that moves with the rotation of the tires is the wheel bearings, and the front differential. If the wheel bearings are bad you will notice top/bottom play if you jack up one side of the car and shake the tire. I doubt its causing the vibration

 

Have you checked your front differential oil at all? If theres any metal in the oil, you could be about to lose a front diff. I've been seeing lots of Phase 2 4EAT's at work lately with bad front diffs

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diffs r fine fluid looks good and no metal ............ so can the rear transmission mount cause this kind of vibrations remembering that the vibrations feel like a out of balance washing machine especially when i am going up hill ( really bad ) ? and are the DOJ's the axles sorry i'm not a mechanic ....... thanks again for all the help everyone

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diffs r fine fluid looks good and no metal ............ so can the rear transmission mount cause this kind of vibrations remembering that the vibrations feel like a out of balance washing machine especially when i am going up hill ( really bad ) ? and are the DOJ's the axles sorry i'm not a mechanic ....... thanks again for all the help everyone
DOJ=Double offset joint; this is the inner joint on the axle that attaches to the transmission. CVJ=Constant Velocity Joint; the outer joint on the axle that goes through the wheel hub.

 

And no, a worn transmission mount will not have the vibration go away when you take your foot off the gas. That doesn't mean it shouldn't be replaced, but it's not the cause of the on/off vibration with on/off gas pedal.

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jheat71, I am experiencing similar symptoms. I have teeth broken off in the front differential. Your issue may be different but I just wanted to let you know what my mechanic encountered.

 

Steve

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front diff is very vilent when it go's and the awd will be kicking in and out and banging

 

 

I had the front diff go when I had my 03 Forester XS.. It was an auto the inner seal was leaking and I heard it whine on the highway so I took the quickest exit since I was only about 1 mile from the Subaru dealership.. I got on the road with stop lights.

 

The front diff let go on the lightest of a throttle press.. It will let you know when it's gone! It was undriveable.. anything over 3 MPH was like driving on a rocky mountain.

 

 

I can't find the pictures right now but the the case was cracked, the diff was mixed with AT fluid and it was all over under the hood.

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Speaking of axles...is it common for the spindles on the transmission or wheel bearing to get worn or ruined?

 

 

--Damien

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