P3 Shimmy driving me insane....

[Pierogi Wagon]

Hello everyone or anyone who will listen. I have a beloved 2008 V70 3.2 with 143K on the clock. I really want to keep it to 250K as I know this is entirely possible with a bit of effort. This was purchased almost 4 years ago with just a hair under 100k on it. It was clean, ran strong and looked pretty good for its age. In the last two years I have put a lot of work into it replacing many old, worn, original suspension bits. The following have been replaced in the past 25k ish miles with OEM stuff from FCP (not always Blue Box, but good OEM parts Lemforder, Bilstein, etc):

Inner and outer tie rods
Swaybar endlinks up front
Control Arms
Struts/guts and mounts up front
Shocks in rear
All engine/tranny mounts
Rear swaybar links and bushings
Just two weeks ago:
Front and rear brakes and 4 tires

Here is where the problems start:
While doing the struts a couple summers ago, I noticed the all CV boots were torn. So I figured I would get axles installed. Well, the super precious Volvo (read FoMoCo) reconditioned(!) axles would cost around $1200.00 from the dealer, not installed. Hard no. So I looked for any other possible option and found some on eeuroparts and reluctantly ordered simply because they were all I could afford less than $400 and I had 2 new axles. Cheap Chinese, yes, but new. I had them installed by my mechanic. The shimmy started immediately. As everyone everywhere on line said it would. Since I know these cheap ones could/would be trouble, I had my mechanic save the originals for me. I put them in a box and they sat in my basement for almost two years. I finally resolved to have the originals rebuilt and went with CVJ in Denver (I live in Boston) to do the work because they supposedly did the axles for the KPax race team Volvos. So I packed and sent the axles to Denver, they received them on a Monday morning and had them done and sent back to me that Monday night. They were great about everything, nice work quick turn around reasonable price...
I had the new/reconditioned axles installed and now the shimmy is worse. There has to be someone somewhere out there that has replaced the axles on these things and not had an issue. I have read a few accounts on line where even with the axles purchased at the dealer the shimmy rears its ugly head....I would do be willing to do filthy filthy things to get this resolved already....Anyone have any suggestions?

TLDR: Even with Reman Volvo/FoMoCo axels my stupid car has the shakes. Help!!!?

[RickHaleParker]

I don't see wheel alignment on the list of done.

[pgill]

The Motor mounts on the P3 3.2 is a known wear point

I suspect that your mounts are collapsed

See this link for pictures (its for the LR2 which uses the same mounts as my S80)

https://www.freel2.com/forum/topic32979.html

[dwcatcvg]

Do you trust your control arms? I second the alignment suggestion. They should notice whether your control arms are compromising the alignment, and they should tell you before tightening everything back up. Whoever is replacing your axles might not be making sure the full weight of the car was resting on the tires before torquing the control arm bolts. Another thing to check is the passenger axle carrier bearing--though you would hear something if the axle was flailing around due to play in that bearing.

I think the CV joints in the OEM axles are incredibly tough, and whoever rebuilt them checked for wear and discoloration before putting them back together. I haven't seen anyone complain that the outer joints failed, but I've been told by a Volvo mechanic that the inner joints are fairly common. They have a softer boot, and the rollers can get pretty hot if the grease isn't in place. The symptom from the inner joint isn't usually described as a shimmy - but a clunk or even a hesitation under acceleration. In my case, a very mildly deteriorated inner joint on the passenger axle resulted in a harmonic vibration through the chassis, but only when I was taking a sweeping curve (in one direction, can't recall which) at speed.

If there was no visible pitting or discoloration on the rollers or the bucket of the inner joint, it's almost certainly 100% fine. Mine looked OK when I disassembled the joint, but there was a slight reddish (I'm told it's supposed to be blueish) discoloration on the spider, underneath the rollers. Since these rollers wiggle, rotate, and move in and out, you can see the surface of the spider legs if you play with the roller. The play, or damage, was not in the bucket. It was between the spherical rollers and the spider -- probably far less than a mm, but I could feel it. I will note, also, that the rollers spun perfectly smoothly on the internal bearings, so if I hadn't looked at the spider legs, I wouldn't have found any reason to think the spider assembly was bad.

[dwcatcvg]

One quick follow up: I replaced my right upper engine mount this morning, knowing that the original one wasn't leaking or fully collapsed, but was still compressed considerably from a good, new part. After removing the original, I noted that, while it wasn't fully collapsed, the rubber seal on the bottom of the mount was full of fluid, and the pillow that the engine bracket sits on top of was jammed down hard and wouldn't move back up to its original position. The new mount is a Corteco, from Partsgeek -- it was actually a mount made for Volvo or Land Rover, but with the label scratched out so you couldn't read it. All other markings on the mount are identical. When installed, I marveled at how much higher the right side of the engine seems to sit in the bay. A few revs from the engine, and I was shocked how little movement there was. All of this suggests that a bad mount changes the angle that the passenger side axle is forced to operate in considerably. The stress on the axle, and the stress on the other torque mounts on that side of the engine must be pretty bad. I wonder if the stress on the transmission-side mount is bad, too. I haven't pulled that one out to compare it to a new one. I also wonder what this angle and play does to the differential and the transmission.