Steering wheel shaking when braking...

[Tony500]

above 40/50mph when I press the brake my steering wheel shakes mad. When I'm doing about 30mph and approaching traffic lights I get a pulsating feeling like I'm putting my foot off the pedal and back on ever so slightly.

In the last two months I have replaced
All pads and disks (pagid)
Droplinks
Poly bushes to the rear of the front wishbones
Dust covers for both ball joints

Everything seems tight when checking for wear.



Would a little bit of air in the system cause this or the abs sensor I have had to put a screw in a little because the clip has broken. No warning signs on the dash.

[Clan]

Originally Posted by Tony500

above 40/50mph when I press the brake my steering wheel shakes mad. When I'm doing about 30mph and approaching traffic lights I get a pulsating feeling like I'm putting my foot off the pedal and back on ever so slightly.

In the last two months I have replaced
All pads and disks (pagid)
Droplinks
Poly bushes to the rear of the front wishbones
Dust covers for both ball joints

Everything seems tight when checking for wear.



Would a little bit of air in the system cause this or the abs sensor I have had to put a screw in a little because the clip has broken. No warning signs on the dash.

It is one of the front discs not true for whatever reason . measure the run out and variation in thickness with a dial gauge and micrometer ... Have you hit a kerb when driving recently ? Are the discs mounted on a clean non rusty flange ? Are ALL the wheel nuts done up to 130 nm ?it may be the wheel flange bent . Don't rule out the discs themselves , try genuine volvo ones if all is ok ...

[volvo for ever]

front discs warped

[Tony500]

Originally Posted by Clan

It is one of the front discs not true for whatever reason . measure the run out and variation in thickness with a dial gauge and micrometer ... Have you hit a kerb when driving recently ? Are the discs mounted on a clean non rusty flange ? Are ALL the wheel nuts done up to 130 nm ?it may be the wheel flange bent . Don't rule out the discs themselves , try genuine volvo ones if all is ok ...

I have not checked the thickness yet but will as I though as new disks will be ok. The flange was cleaned with a wire wheel brush before put on. I did the front wheels at 120nm not 130 but don't think that would cause this.

I will order a new slide kit for the calipers too. Think a can contact pagid if disks are not true?

[iainmd]

I'd think about getting your front wheels re-balanced.

[AndyMcc]

Hi, I have the same issue which I started a thread about a few weeks ago. I removed the calliper guide pins yesterday, which were a little stiff - this will have been the first time since new - however it's still the same.

I'm surprised nobody has come forward with a straight solution to what would appear to be common problem. I don't really want to start throwing money at it in the hope of solving it if that makes sense.
The link is below

http://www.volvoforums.org.uk/showthread.php?t=229616

Good luck
Andy

[benrpatterson]

I have the exact same problem on my S40.

I can see the various forums are full of such issues, with no clear culprit...

Reluctant to spend any money on it as yet to get it fixed.

Do let us know if you get to the bottom of it.

Thanks
Ben

[Tony500]

Got a early finish in work tonight and came home and checked the disks... they were fine.
I taken off both disks and wire brushed the inside and the face of the hub, changed the front wheels to the rear wheels and taken a drive and it feels better. I do need to get the front wheels rebalanced now though.

The car now drifts off to the left now... and have more feel and noise with the different tyres up font.

Its never ending lol.

Worth giving it a wire brush or if you have a drill and wire wheel

[Nick Warwick]

I found out when i had this problem it was a slight buckle in the alloy.

[Tony500]

My problem is the cv case that inserts into the gearbox is loose.

Will need to see if the bearings is ok