2002 XC70 Shaking Under Load

[kef]

Hi All,

My 2002 XC70 at 200k+ miles has had a strange engine shaking problem when accelerating/taking off from a stop and at low speeds. Shaking goes away at higher freeway speeds (60+ MPH) OR it is not noticeable.

I've replaced all of these parts...

- ALL bottom motor mounts including top torque rod mount, bottom transmission torque rod. Also replaced the front right mount under the T-belt.
- Both front axles
- Control arms
- Shocks including seats and bearings
- Steering end components
- Ball joints
- Bearings
- Replaced angle gear oil (no leaks)

There is no engine problem (misfire, etc).

I know the shaking is not coming from the middle or the back of the car... Here is what I did to see where the shaking is coming from...

Raised all 4 wheels off the ground and had an assistant run the car. As the car accelerates (in gear), I can see from under the car the engine shaking as if a motor mount(s) is loose. I re-tightend the mounts just in case (they were tight to begin with). Ran the same test, and still the shaking was present. One odd thing I noticed was that all 4 wheels start to turn when in gear, but the front right eventually stops turning. Looking at the front right axle at the point where it comes out of the angle gear casing, I can see the seal around the axle rotating, but the axle remains stationary. Is this telling me something? Is the collar suspect? Does the collar have anything to do with the front right axle? [The front calipers are new and breaks are not binding]

Are the new mounts (especially the rear one) suspects?

Appreciate any inputs you can provide...

The car is a bit over 200k miles, but it is well kept, and not abused. I'm stumped! It makes quick acceleration from a stop a pain with so much engine shaking.

Appreciate your inputs...

-Kef

[volvospeed70]

The right front axle is what goes into the collar of the angle gear and in turn sends power to the rear wheels. I could only guess there may be an issue with your angle gear collar.

[gary g]

Sounds like it could be a coil maybe, but it would not explain the axle rotation. Couldn't hurt to check the plugs for any sign of a bad coil.

[Tahoe_XC]

Could be wheel balance issue...

[kef]

Thanks all for the inputs...

-Wheel balance ruled out -- Engine shaking with old and new tires (balanced); shaking happens at low speeds; shaking seen and felt in engine bay/cabin, but not felt through steering wheel.
-Coils ruled out -- Engine is in top shape, no motor shudder, no hesitation, no misfire, etc.

-The Collar: How do you troubleshoot a bad collar without removing the angle gear casing off? [I'm trying to find out why the whole engine shakes when it is under load/in gear]. If the collar is bad, why would I have power going to the rear wheels. If you recall, I had raised all 4 wheels off the ground and had the car run. All 4 wheels start turning, but the front right (passenger side) stops turning (don't know why). This is when I found out the whole engine shaking as if something is catching and releasing or warped...

I've driven the car for over 10k miles in this condition (shaking/shuddering at low speeds), but mostly on freeway speeds. The shaking is not noticeable or is gone at higher speeds (60+ MPH). Nothing has gotten worse or better.

I'm thinking I will need to pay a mechanic a visit, which is usually not my first choice. If anyone out there knows an independent Volvo mechanic in Albany/Saratoga Springs NY area please let me know.

Thanks!
-Kef

[2002V70XC]

have you ruled out the the strut bar holding the engine? My car had little shakes that caused by the strut bar being loose at the 2 ends (the long bolts that hold the bar against the mounts at the strut tower). Maybe you can just test and see if your strut bar is loose or tight to rule it out!

[kef]

Took a quick look at the the bolts and bushings of the strut bar mount brace. The bolts are tight, and bushings appear to be intact-- I grabbed the strut bar and twisted it front to back, and does move back and forth, but I think it is supposed to do that. Not sure how much of the movement is normal. It has no movement laterally (left to right). That said though, I will loosen the torque rod mount and test drive it. We'll see...if it gets worse or does something interesting...

I'm wandering now: What are the symptoms if the front differential (within the transmission) goes bad? Is engine shaking (under load) part of the symptom. Is there anyway to tell how it is operating? Does it send out codes?

Still looking for a trustworthy Volvo mechanic in Albany/Saratoga Springs, NY vicinity... if anyone can recommend one... Thanks!

[kef]

An update on a test:

Loosened the top torque rod bushing connection and drove the car to see if the shaking would change (get worse or better). No change. The shaking is still there at low vehicle speeds. I've found an independent mechanic, and will see what he has to say. I'm just at loss as to what could cause the whole engine to shake under power at low speeds -- even after replacing so much of the front end part of the car.

[JRL]

Why would you go through this for so long and not take it to a mechanic?
I fail to understand this (non) logic and a huge waste of your time

[vtl]

Have you tried to disconnect VVT solenoid?

[kef]

Have you tried to disconnect VVT solenoid?

What do I expect to notice when the CVVT is disconnected? Would the behaviour be different under load, no load?

[kef]

Why would you go through this for so long and not take it to a mechanic?
I fail to understand this (non) logic and a huge waste of your time

My explanation to why I have not visited a mechanic for my problem may not be logical, but it is this: I have not had good luck with mechanics in my past experiences. My current XC70 is my fourth Volvo, and I have driven the previous ones (740, 740 turbo, S70) past 300K miles without a visit to a mechanic, minus wheel alignments, tire changes, state inspections... I suppose I was lucky to have had no major engine or transmission problems. I've also received a ton of help from online folks like you in the past to resolve my problems... I also hate to find a new problem after a repair at a shop. If I tackle the work, I know what I've worked on, what I touched, where I've been. Not to mention the satisfaction of doing things yourself!

That said though, I have plans to visit a shop in Saratoga Springs as soon as time allows...

[vtl]

What do I expect to notice when the CVVT is disconnected? Would the behaviour be different under load, no load?
Under load. V70's engine was resonating in 1400..1650 RPMs range.

[Steve F]

I wonder if there could be a problem with your flex plate? Unusual certainly, but that could produce the vibration you describe. I'm just assuming there is a flex plate, I've never seen the transmission apart

[kef]

I wonder if there could be a problem with your flex plate? Unusual certainly, but that could produce the vibration you describe. I'm just assuming there is a flex plate, I've never seen the transmission apart

Hmmm, flex plate! Well, we shall see. I dropped off the car at a shop today after an explanation of what I've done so far.

I'm thinking though...If flex plate is bad/warped, it should have an effect on the angle gear collar. I suppose a good test would be to disconnect the drive shaft and take it for a drive a FWD. As I don't have a good place to work on the car at the moment, the test would have to wait. But can't wait to hear what the shop thinks is the problem...

[kef]

I got the car back from the shop after 'diagnosing' the shaking problem. Their thought is that front axles exhibit a wabble and they should be replaced first... I had mentioned to them that both axles are fairly new (April - May 2014). Passenger side was actually replaced 3 times because of leaky inner boots. Driver's side was replaced ones (April 2014).

Now, a question: Is it possible to damage or make axles 'untrue' due to over-steering? I'm asking this because the new control arms I put in January 2014 do not come with steering stops (https://www.fcpeuro.com/products/volvo-suspension-control-arm-left-xc70-v70-xc-30635231my). And they don't have any place to bolt one on. Is this OK for XC70s?

Another question: Is it possible for the rear drive shaft to exhibit shaking problems under load. Remember that the engine is what shakes under load. I don't feel shaking coming from the rear, only from the front of the car. Could U-joints in the drive shaft exhibit engine shaking problem? One other piece of information: There is always a small lag when I engage the gear from park to drive or reverse.

[Thames]

Small lag from P to D (and R) could be a sign of valvebody failure...

[hoonk]

Their thought is that front axles exhibit a wabble and they should be replaced first... I had mentioned to them that both axles are fairly new (April - May 2014).

And they don't have any place to bolt one on. (steering stops) Is this OK for XC70s?

There is always a small lag when I engage the gear from park to drive or reverse.

1. What brand of axles have you been using? The aftermarket axles I tried have about a 40% success rate, the new aftermarket axles are usually worse (vibrate as much or more) than the old axle being replaced. Unfortunately Volvo wants about $615 for a right AWD rebuilt axle! (but 100% are good out of the box)


2. There are no steering stops on the xc70, v70-r70-s60do have steering stops.

3. You could try simply erasing the adaptation, (if you have access to VIDA) and see if the transmission figures out a better shifting pattern and if you have time have the control unit set into the adaption mode to get the control unit to determine the best shifts.

[kef]

1. What brand of axles have you been using? The aftermarket axles I tried have about a 40% success rate, the new aftermarket axles are usually worse (vibrate as much or more) than the old axle being replaced. Unfortunately Volvo wants about $615 for a right AWD rebuilt axle! (but 100% are good out of the box)


2. There are no steering stops on the xc70, v70-r70-s60do have steering stops.

3. You could try simply erasing the adaptation, (if you have access to VIDA) and see if the transmission figures out a better shifting pattern and if you have time have the control unit set into the adaption mode to get the control unit to determine the best shifts.

Hoonk, Very good info, Thanks!

Axles were Empire brand from FCP. I will definitely replace them one at a time.

As for shifting... the car shift perfectly; it only has a lag when shifting from park to D or R. It is really not a big problem, I was mentioning it to see if that may have something to do with axles or drive shaft U-joints. There was a mention that the lag may have to do with valve body problems. I will keep that in mind...

[kef]

Replaced the driver's side axle with a part from Advanced. I just wanted to see if there will be some kind of toggle.

The first time I test drove the car, I thought wow, the problem is gone! Well, not so fast. After a 20 minute test drive on the freeway, and going at slower speed, the shaking/vibration came back again.

Now, my question is, why was it good the first time, and bad the next time? Right after the axle replacement, that is. I don't think the cause of vibration is the front axles....the driver's side is the 2nd axle, the passenger side is the 3rd axle I replaced, but all with the same result.

A note: Sway bar bushings are shot.
Another note: If I accelerate (drive) the car while steering continuously LEFT, the shaking/vibration goes away or is not noticeable.

[kef]

I had another mechanic test drive the car today while I sat next to him. I confirmed that the shaking/vibration is coming from the driver's side of the car, I felt some but definitely it is coming from the left side.

The mechanic kept on saying it is definitely coming from the drive train. I explained that I had just replaced the driver side axle. Then he was suspecting the transmission - output bearings, etc. He then put the car on a lift and checked things around. He noticed that there was some play on the left side, and suspected bad ball joint but realized that they were new. He then looked into the steering rack. Indeed the play was coming from the steering rack; not the obvious play of worn out teeth, but an up and down play in the rack as you move the wheel side to side. No play on the right side of the rack or ball joint.

Now, that is new stuff--not connected to the drive train. So the question goes: What does the steering rack have to do with the front left of the car/engine shaking under load? The shaking is NOT felt in steering wheel. You feel it in your legs on the driver side.

[Antherzoll]

Maybe of some interest.

http://www.volvoxc.com/forums/showthread.php?17630-Steering-Rack

[vtl]

It could be a crappy tire or shot front LCA bushing(s). My XC70 had annoying vibration, cured with new LCA bushing pressed in. Then few months later slight vibration came back. Bushings are in a good shape, I took the struts out, disassembled and inspected, all good. Swapped tires between front and back, vibration moved to a back of car. Did balancing in two different shop - no luck. It almost goes away with tire pressure at 40 psi, so I suspect worn/damaged tire, they are at 40k miles now and very close to end of life - won't drive for more than a month or another.

Your mechanic can be right too: slight play in steering rack can be a cause of vibration.

[skibo]

I had new Empire axles put in a few months ago and immediately picked up a very similar vibration - the tech thought the inner joint on the new right axle was to blame, and then within a month that very joint started to throw grease. At this point I'm living with it, but I hate it. I may have the OEM axles I saved rebuilt for when this new grease-less joint starts to make noise. Should be any month now.

[kef]

Just came back from a 1200 mile round trip... I drove when there was less traffic so I could maintain 65+ MPH in order to avoid the engine shaking. The car held fine. I obviously did not punch it too much at take off or at lower speed as I hate to feel it shake so much.

Coming back to the nagging problem...
- Shaking still present at lower speeds
- I still think it is not the axles. [replaced several times]
- I do not suspect the steering rack because there is no vibration/shaking in the steering wheel]

Now, my suspicion is subframe bushings. Here is why...
- I had added IPD's polyurethane inserts back in March, but did not see considerable improvement in road handling, may be a little. I'm thinking there might be some kind of subframe play.

I made a video of the 'engine shaking' and posted here: http://youtu.be/mQVcTxBR8X4
LED flash light apparently had some kind of flicker, but try to look at the actual shaking starting from the 2nd gear onward. I have a longer video I can post if needed. But this video is enough to show the engine shaking, and not the axles. And yes, the top torque rod mount is new.

Your inputs...

[Antherzoll]

Maybe it's me but I can hear quit a bit of hissing on load. Have you checked for vacuum/boost leaks?

[kef]

Maybe it's me but I can hear quit a bit of hissing on load. Have you checked for vacuum/boost leaks?

I have not checked for vacuum leaks because the engine idles perfectly without hesitation and sounds fine at high rpms (without load). Are you saying the behavior will be different under load (if there is a vacuum leak), enough to have some 'oscillation'?

[Antherzoll]

Under load you will create pressure in the intake piping, that is something you can't do on a standing test without having the car in drive and holding the brake (not recommended).

I can't say it will cause the vibration you're feeling, just a observation, which may be incorrect.

[garycoop]

I'm having almost exactly the same problem with my 2002XC. Have replaced many of the same parts as you . Have you found a solution to this very frustrating problem? My mechanic is at a loss for an answer.

[kef]

I'm having almost exactly the same problem with my 2002XC. Have replaced many of the same parts as you . Have you found a solution to this very frustrating problem? My mechanic is at a loss for an answer.

I have not resolved my shaking problem yet. However, I'm chasing these ideas now:
1. Re-mount the rear motor mount. I had a hard time putting it in place when I replaced all mounts. Perhaps, it is not seated right...
2. Replace all subframe bushings. I know I have installed those IPD polyurethane inserts, but with so so improvements. My thoughts are that a the whole cradle may be shifting/twisting a bit under torque creating bad angle for the left axle mainly. I also noticed that the car veers a bit to the right when I do a controlled punching (acceleration).

If only I have the time to do it...

[briss]

An update on a test:

Loosened the top torque rod bushing connection and drove the car to see if the shaking would change (get worse or better). No change. The shaking is still there at low vehicle speeds. I've found an independent mechanic, and will see what he has to say. I'm just at loss as to what could cause the whole engine to shake under power at low speeds -- even after replacing so much of the front end part of the car.


Just following up to see if you have found the problem. I have a similar problem and have taken many of the same steps but yet to solve the problem.

[kef]

Just could not find the time to work on my car. Strongly think subframe bushings as main suspects. I will also check on the condition/seat of the rear mount just in case. I'm also considering mounting a camcorder in suspect areas of shaking. Time...

[garycoop]

I disconnected the variable valve timing solenoid on the slight chance that could be causing the vibration. Drove it for a few days and still had the problem. Oh well....

[kef]

garycoop and briss,

Have you raised all four wheels off the ground and run the car and noticed engine shaking? If you can do so, that would be very good info. In my case, the engine shakes badly with all wheels of the ground, in gear and when accelerating. I'm still at loss what would cause that, or if that is normal on AWD systems. So your test would be nice to have...

Thx!

[garycoop]

kef

I have had the car up on a hoist and run it. My mechanic did not notice a lot of engine shaking but I did have problems with a front tire. I needed new tires and all four were replaced. This corrected the tire problem but we still had the car issue ie shaking on acceleration.

He felt it may have been front half-shaft related although the shafts were only a couple of months old. He asked for warranty from the supplier and we changed to new shafts a couple of weeks ago. The vibration improved considerably but there is still some, Strangely, it seems to be more when the weather is cold. Thought about the remaining 2 engine mounts which may be next. Will see if the temp difference holds up over time. At least it is not really irritating anymore. My mechanic has been most understanding.

[kef]

Thank you, garycoop. Apologies for taking so long to reply and follow up with my shaking problem.

Well, I had some time today, and looked at a couple of interesting things...

I was able to reproduce the shaking symptom after raising the front wheels and rotating one with my hand. Look at the video here: http://youtu.be/LISciexfux4

While rotating the wheel(s), I could feel resistance consistently at one periodic spot; and that resistance makes the whole engine jump slightly, thus I think the shaking I feel when driving. I can only think the problem is coming from the transmission, but I don't know what part of the transmission would create some sort of binding or unevenness during rotation. There was a mention of a flex plate by Steve F a while back. Frankly, I don't have a diagram of the inner workings of the transmission. I was hoping someone could comment on a possible flex plate problem.

Another thing I observed was some level of play at the point where the driver side axle connect to the transmission. The axle is fairly new, so I don't think it has anything to do with the axle. But level of play bother me. Here is a link to the short video clip: http://youtu.be/h0wKDFC65Lk

As for mechanics' diagnoses, their inputs are all: "start changing the front axles again, then, check the rear axle, etc." The fact I had replaced a lot of front end parts on a car over 200k miles does not encourage them to work on my car anyway. I may end up driving it until it completely fails if the problem comes from the transmission. But with the engine, body and interior in such good shape, I would hate to let it fail at this time.

Thanks!

[Astro14]

Front axle.

There is nothing inside your trans that will cause the periodic binding that you've discovered.

Just because the part is rebuilt doesn't guarantee that it's working properly. The success rate with Chinese rebuilds is about 50%.

[kef]

My shaking problem is all gone, and happy to finally close this post! Thank you garycoop, Astro14 and ALL for steering me in the right direction.

The fix: Passenger side axle replacement - 4th axle! I'm hoping this one will last. Indeed, the success rate of the after market axles I replaced is really poor--I just could not accept that fact after replacing the axle several times. It goes to show that 'data is king'.

Thank you All, again!
-Kef

[Thames]

Great !

What was the axle brands ?

[kef]

Great !

What was the axle brands ?

Well....The passenger side axle I just put on is 'tough one' brand from Advanced. This is the 3rd one from them within 8 months. The very first one I replaced was 'empire' brand from FCP, which had a problem. So, I settled on a local purchase rather than on-line ones.

[vtl]

I've got two driver side EMPI axles from FCP, no shakes. Of course, it doesn't say you'll get a good one too :)

[Tonyx]

Thank you, garycoop. Apologies for taking so long to reply and follow up with my shaking problem.

Well, I had some time today, and looked at a couple of interesting things...

I was able to reproduce the shaking symptom after raising the front wheels and rotating one with my hand. Look at the video here: http://youtu.be/LISciexfux4

While rotating the wheel(s), I could feel resistance consistently at one periodic spot; and that resistance makes the whole engine jump slightly, thus I think the shaking I feel when driving. I can only think the problem is coming from the transmission, but I don't know what part of the transmission would create some sort of binding or unevenness during rotation. There was a mention of a flex plate by Steve F a while back. Frankly, I don't have a diagram of the inner workings of the transmission. I was hoping someone could comment on a possible flex plate problem.

Another thing I observed was some level of play at the point where the driver side axle connect to the transmission. The axle is fairly new, so I don't think it has anything to do with the axle. But level of play bother me. Here is a link to the short video clip: http://youtu.be/h0wKDFC65Lk

As for mechanics' diagnoses, their inputs are all: "start changing the front axles again, then, check the rear axle, etc." The fact I had replaced a lot of front end parts on a car over 200k miles does not encourage them to work on my car anyway. I may end up driving it until it completely fails if the problem comes from the transmission. But with the engine, body and interior in such good shape, I would hate to let it fail at this time.

Thanks!

Kef,
Thanks for your videos of diagnosis. That one where you make the engine move turning wheel by hand was ingenious. I will follow up on this myself as I have the vibration issue too. Thanks again.

[Steve F]

You can disregard my suggestion of the flex plate at this point, it would not produce the symptoms you've described in your last post. A flex plate vibration would vary with engine speed whether the car was moving or not and that doesn't seem to be your case.

[garycoop]

Finally! Found the reason for my vibration! After the third right cv axle, no more vibration and it feels so good. The third axle was a Volvo axle and the first two were aftermarket. Wanted to post the result as I read so many posts where there are questions asked but no solutions posted. Hope this can help someone else with this very annoying issue.

[kef]

Wonderful! Apologies... In my case, it was either the 3rd or the 4th front right aftermarket axle that fixed the vibration problem.