Under carriage noise 2002 XC70

Post by **precopster** » 07 Feb 2016, 11:14

We were no more than 5 minutes drive from home from a big weekend trip to the ocean and an overnight stay when a cocophany of scraping noise appeared from under the car while rolling. It was not acceleration dependant or coming from the engine.

Sounded like metal on metal and definitely got worse over 25 metres until we decided to catch a cab home. Feels and sounds as if it originates from the tailshaft. Could be the angle gear. Worst sound I've ever heard from our cars

Has anyone had angle gear failure and if so was it sudden?

Post by **vtl** » 07 Feb 2016, 20:49

Check if driveshaft is rubbing exhaust or there a rock between brake rotor and dust shield.

Post by **precopster** » 07 Feb 2016, 21:19

Had the car towed to the closest garage as I suspected an angle gear or tailshaft problem.

Turns out it's the LHS front bearing which gave no warning and just imploded. They want $685 to repair with used parts because they want to replace the axle shaft as well. I don't see how the axle shaft could have been affected by 25m of driving on a bad front bearing.

I bought a new axle bearing for $165 and will be paying them no more than 1.5hrs of labour plus wheel alignment (also not really necessary if they place the strut back where it belongs) but I will have it done anyway.

Post by **precopster** » 09 Feb 2016, 06:26

Dropped in at the workshop this morning with a new Meyle wheel bearing and was asked to bring in the axle shaft as well. I asked to see the damage to the axle shaft and was led to the workshop where the car was still on the hoist.

One of the axle bolts had simply loosened and had rubbed on the very edge of the CV cage. The bolt head was lightly chamfered by the scraping with plenty of edge left for tightening. I really started to question the mechanic as to why he wanted to replace the axle shaft. He also wanted to replace the axle carrier because he said the whole assembly is now "unsafe" due to the stress it has sustained.

I was having a very interesting conversation with him when he started using heart attack patients as an analogy. When I told him I wasn't interested in hearing an analogy to a heart patient as this was obviously not a human body and that I highly doubt there is any damage to any other components the shop manager interrupted, flew into a rage and told me I wasn't welcome there.

I'd obviously uncovered something about their work ethics because I too was really beginnning to feel that I was about to be robbed or deceived.

Pics below tell the story. Last pic shows the axle before I touched it.

The old bolt was re-used with plenty of grip for torquing and as the thread was almost perfect with no burrs I was very confident I was not compromising anyone's safety.

JeffHicks · Post by **JeffHicks** » 09 Feb 2016, 06:55

With a drop of thread-lock, that bolt (and bearing assembly) will last far longer than you own the car. Glad you caught them on it.

Post by **vtl** » 09 Feb 2016, 08:13

It's a well-known fact that you walk on heads in Australia. Is it also legal there to punch bastards in face?

Post by **precopster** » 09 Feb 2016, 13:04

I should have at least jacked it up and looked at it on that night it happened but that noise sounded like exiled angels.

What annoyed me most is that there was no mention of a loose bolt; they only told me that the bearing had failed which is not the case.

At the very least a new bolt should have been quoted if they wanted to cover the safety aspect.

The other three bolts were far from tight enough so I figure the bearing was replaced or just not tightened properly on the production line. I noticed that all the aftermarket bearings don't come with new bolts. The genuine Volvo bearings do and also provide a dust boot.

I launched an online complaint with Bridgestone yesterday and expect a call over the incident from a head office rep though I don't expect anything to come of it because the guy on the end of the phone will probably have no mechanical aptitude or he will take the word of the workshop when they cite "safety first"

nsjames · Post by **nsjames** » 09 Feb 2016, 13:10

i've never replaced the bolts on a unit bearing, and I've done plenty of different ones.

i've never seen one that was torque to yield, or even in that realm of torque required. Do the volvo bolts have thread locker pre applied?

Post by **vtl** » 09 Feb 2016, 13:16

Yes, Volvo has red/permanent thread locker preapplied on all large bolts.

Update: well, I lied. That one is TTY bolt and it does not have a thread locker.

Post by **precopster** » 09 Feb 2016, 13:17

FCPs site lists the genuine bolts with a pic with no thread locker https://www.fcpeuro.com/products/volvo- ... hub-983072 and has a description saying they're torque to yield but like a lot of bolts on Volvos they are so well made that reuse is not absurd. As they weren't torqued properly in the first place I still consider these to be new.