Metalic knocking in time with tire rotation on passenger side

dasper252 · Post by **dasper252** » 21 Oct 2019, 17:08

I have a 2005 XC90 2.9T, 122,000 miles. The knocking started very soft then got louder over the next 10 miles. The knock is in time with the tire rotation, i.e. becomes faster as speed increases and louder but only to a point. If a speed of less than 15 is maintained the intensity of the knock stays the same. At higher speeds it become so rapid it is hard to hear it. Strangely while driving back to the house, I went around a banked corner about 45 mph to the right and the knocking disappeared. The next day I drove the car about 20 miles and it did not know, However It came back a day later and did not go away this time. Any suggestions are greatly appreciated.

Post by **SuperHerman** » 21 Oct 2019, 21:53

Look at your CVs - could be a torn CV boot with contamination. Check you tires for a rock or similar. Maybe a dust shield?

Post by **oragex** » 22 Oct 2019, 04:48

As above, and I would also quickly verify wheel lugs are properly secured and maybe remove the wheel and look at all caliper bolts, bearing bolts. I would certainly pull asap in a garage for a quick inspection of everything in there, including all securing bolts

dasper252 · Post by **dasper252** » 22 Oct 2019, 12:34

Thanks you both. Great suggestions. I followed them, removed tires, inspected boots, brakes, dusty shields, no play in the axles. Replaces tires, torqued to specs. Check trx fluid, good. Test drove, heard the sound for only a moment, very faint. Drove ` 5 miles, various speeds and road conditions. Knocking did not return. This is turning out to be one of those "unable to duplicate" things I hate so much.

Unless there are other thoughts, I will keep you posted should or I mean when it returns steady.

Post by **oragex** » 22 Oct 2019, 12:39

Upon removal of the wheel, did all wheel bolts feel they where tight enough ? I will verify them again from time to time just in case. There are factors that can cause wheel lugs to break loose while driving, such as a slightly bent wheel or bent wheel bearing plate.

dasper252 · Post by **dasper252** » 22 Oct 2019, 14:42

I did take notice and the were tightened to what seemed to be spec. 105 lbs is what I read should be. Thanks I will retorque from time to time.

Post by **Roger_850T** » 26 Oct 2019, 21:53

At least you have been able to narrow it down to related to wheel speed!

It may be that the lug nuts were not tight, or there was something hitting, that was dislodged when you removed/replace the wheels, so it's plausible that you may have fixed it.

If it comes back, maybe rotate tires around? See if you can get the noise to move, or prove that it doesn't move.

Disappearing when you turn to the right suggests a hub on the right side is failing, and the noise goes away when the weight on the hub is reduced during a right hand turn. I wouldn't start by replacing the hub, but you may get here by ruling out other things.

Double-check for a stone/nail/??? in the tire?

Hope this helps!

Roger

dasper252 · Post by **dasper252** » 28 Oct 2019, 09:21

Thanks Roger,

I drove it nearly 400 miles this weekend. The noise would be very faint for a while and this go away. It is probably going to have to catastrophically fail before I can id it.

Post by **abscate** » 28 Oct 2019, 09:57

The good news is if it goes faint, little/no damage is being done.

I am definitely thinking CVs for this. You might have to open them up and regrease them. A nasty job but at least its cheap

dasper252 · Post by **dasper252** » 19 Jan 2020, 10:06

UPDATE: It turned out to be the front CV joint on the drive shaft where it connects to the transmission.