2005 XC70 100k miles intermittent shaking in drivetrain(?)

**JRL** · 04-13-2013, 07:41 AM

You can't do it that way
Drive the car.
Make 35 MPH medium sharp turns and report back what the noise does.

A bad wheel bearing will make more noise on the opposite side of the turn.

ie: left turn, the noise will come from the right side and be louder (weight jacked to the right, more load)
The other way is to jack the car up, run it and listen wheel by wheel, for noises

**PierreC** · 04-13-2013, 09:02 AM

Originally Posted by VolvoDaddy

If I kick the top of the tire , the chassis will yaw about 4 cycles. Wife's xc90 only one cycle with 18 inch 55 series tires.

Worn shock absorbers can possibly lead to the intermittent shaking (un-dampened resonance) and the above quoted symptom also point to shock absorbers.

As far as the intermittent shaking is concerned, also check the REAR shock mounts. The front shock mounts get a lot of attention as they need occasional replacement, but the rear shock mounts tend to get neglected. [I had an intermittent shake on my 850 a few years ago, which was cured by replacing a failing / failed rear to shock mount.]

**mapper** · 04-18-2013, 07:22 AM

Wow, all over the map here.

Start by rotating the tires. If the vibration moves that means its a tire.

**VolvoDaddy** · 04-19-2013, 02:11 PM

The plot thickens...

So I rotated the tire and it definitely made a difference... vibration moved toward the front. Noticed that one of the back (now front) tires has a tread misalignment where the mold lines meet. The other tire is definitely out of round... was scraping the ground for half the rev, and not the other half. So tires are definitely an influence... tirerack for some 17" ers ... here I come.

Being perplexed, and somewhat pissed off at the car, I was flogging the car on the exit ramp cloverleaf, hard right turn at about 50 mph, and there was a "pop". Now my suspension seems to actually work! Much better... about as good as my Saab. Still need to look and see that everything is alright under the car.

Either some crap (rock or something) in the suspension? Stuck shock? Stuck differential? Spring wasn't set right?

FYI, when installing my hitch last month, I did jump up and down on the rear suspension... they seem to work. haven't check out the front... pushing hard on the front fender is not good since it's fairly thin sheet metal, but I still need to try it on the bumper. I'm also going to go side to side hanging off the roof rack and feet in the rear door.

Thanks for all your help... would like to write up a FAQ eventually.

Cheers, J

**JRL** · 04-19-2013, 02:23 PM

Possibly a spring re-seated itself but the big thing it seems as if you need tires (all 4)
Also you need to know that at about every 100K miles or so many of these (actually most) need either a partial of a full suspension rebuild.

If you drove my 07 with 116K miles you would swear you were driving an almost new car, but I rebuilt the ENTIRE suspension when I bought with 110K miles.

**VolvoDaddy** · 04-29-2013, 03:39 AM

@JRL, Nice ride! When you say you rebuilt the entire suspension, do you mean shocks, controls arms, bearings, etc? Is there a kit you can order?

So I discovered that my upper engine mount was quite loose, even though it looked new. It had play in all 3 axes. Upper and lower mounts on order now. I jammed some washers in to tighten up the fore/aft axis, and car definitely felt more "connected" to the road versus "floating". Sensitivity to small bumps was less, but not gone... still need to work on the tire aspects.

After mounts, will take to dealer for suspension look, mount, balance, then fix what's needed and new tires/wheels.

Will keep everyone informed... FYI, I should have started with the upper engine mount...

Cheers, J

**VolvoDaddy** · 05-01-2013, 05:53 PM

Upper and lower mounts replaced. Car fells better, but no effect on vibration. Rained today and seemed worse. Taking to mechanic Friday.

**zuruduckydoo** · 05-07-2013, 08:04 PM

Hi

I have a 2001 V70XC (133K miles) doing what appears to be the exact same thing. Living out in the country, I describe it as driving over a dirt road after a Caterpillar tractor left a trail in the the mud--and it dried hard. I've had my local Volvo indie mech crawl all up in the front end, I've taken it to the tire place that has the super machine that checks the wheels not just the tires, I've had it aligned--nada zip zilch. Nothing is wrong that anyone can find. They all agree that it shakes like crazy, until you take your foot off the gas or pop it into neutral. Then it's fine. I have noticed it is usually around 60 mph or 80 mph, SOMETIMES, but not always, also accentuated when in a tight turn (say, on an on- or off-ramp). Unnoticeable in town, I would imagine due to lower speeds. The only thing that anyone has suggested is axles, but as something to change out, and I've been wondering if this is the best first part to throw at it.

Hopefully unrelated, the car started up in my driveway in limp-home mode today, with no warning or issues on the 30-mile drive home. I've posted on another thread about this, but while it is in the shop tomorrow I'm gonna ask the mech to check out some things on this thread for the shaking that I do not think have been done. If we find anything I'll let y'all know.

**sjonnie** · 05-07-2013, 08:19 PM

Originally Posted by zuruduckydoo

The only thing that anyone has suggested is axles, but as something to change out, and I've been wondering if this is the best first part to throw at it.

Yes, it's axles. Most likely the drive shaft, but there are clearly other components interacting with it, possible engine mounts or worn suspension components. Either spend $$$ or learn to live with it.

**VolvoDaddy** · 06-06-2013, 12:49 PM

Sorry for the long time between updates, but car has been frustrating.

Two mechanics have looked at suspension, and said tires "need to wear in"...

So replaced the stock 16" rims with brand new tiers with 17" and 235/55-17 from tirerack. Handling much better now! One tire was out of spec, so took a while to get that fixed. On smooth roads, smooth.

Still:
1) xc70 has "sensitivity" to small bumps.
2) After "michigan left turn" and hard acceleration, shakes like unbalanced (50-70 MPH), then eventually goes away after about 5 minutes. If no turn and gentle acceleration, seems OK. Also seems better on turns versus straight... straight small unbalance will "show up" then go away.

So: Right lower motor mount just arrived today.

Next is to take it to dealer and let them look over entire car.

Any other suggestions?

Thanks!