South Wales Volvos

slippy · Posted: Sat Jan 10, 2009 10:27 am Post subject: worrying knocking

Model: S40
Year: 2000
Engine: 2.0 lpt
Auto/Manual: manual
Mileage (approx):90k

I have a knocking noise coming from the front drivers wheel, or so it seems.
At first i thought it was balancing needing doing, but the balancing has been checked on all 4 wheels and the symptom is still there.

It started faintly a few weeks ago and has gotten much more noticable.
I dont get it every time i hit the speeds mentioned, but reasonably frequently.
It comes on at around 65-75 mph.
If i slow down sometimes it smoothes out by 60, sometimes it is still knocking at 50 !

The feeling through the floorpan and peddles and steering wheel reminds me of when i had a loose caliper many years ago on a vauxhall.
I have the wheel off and can see nothing obvious, and the caliper is definately not loose on this car though.

Any ideas chaps ?

Colin · Posted: Sat Jan 10, 2009 10:55 am Post subject:

Does the knocking happen with every wheel rotation or just when you hit a slight rough patch on the road?
With the wheel off the floor, can you move itup/down or left/right?
With the wheel on the floor and handbrake on, are you able to roll the wheel forwards/back?
Suspicion is to do with the bushes, but you'd expect it to happen at lower speeds too.
Other suspect is CV joint or track rod.

Aah, check the security of the pads in the caliper. It's possible that one of the pistons has stuck and the pad is loose.
Failing that, I can come up and have a look if you like as I'm only in Newport.

Cally · Posted: Sat Jan 10, 2009 1:22 pm Post subject:

Also worth taking a look at the drop links as they are fairly commom on the s40 althouth would expect them to make a noise at lower speeds as well

slippy · Posted: Sat Jan 10, 2009 3:03 pm Post subject:

Cheers guys, this gives me some avenues to investigate.

I dont have any flat ground near me so I will have to try and get her up on some stands at a firends house soon.

slippy · Posted: Wed Jan 28, 2009 5:04 pm Post subject:

The car needed other attention and ended up in a local garage.
i had all the things you advised checked out and nothing looked out of place.

Took her home.

For 2 days the car did not act up, but then on the third day it came back.
it feels like just the front drivers wheel is on cobbles!

I have had a look around and get the impression it may be the _inner_ CV joint.

I am getting this looked at next, wish me luck...

Colin · Posted: Wed Jan 28, 2009 9:09 pm Post subject:

Dude, gimme a shout if you're unsure as to what the problem is.

fox88 · Posted: Thu Jan 29, 2009 11:15 am Post subject:

The bearings in the strut top mounts are a common problem, Ive recently changed mine, didnt quite have the same symptoms as you tho, but theres not really anyway of checking this with out dropping the whole front strut, and also you cannot buy the bearing you have to buy the whole strut top mount....not cheap!!