Steering wheel shakes when braking from high speed

Steering wheel shakes when braking from high speed

Author
Discussion

TameRacingDriver

Original Poster:

18,079 posts

272 months

Friday 5th July 2013
quotequote all
What would cause this then? If I'm braking from say, 80+ the steering wheel shakes and there is a distinct lack of braking power. It does not happen at speeds below this.

I did think warped discs but why would it just happen at speed?

300bhp/ton

41,030 posts

190 months

Friday 5th July 2013
quotequote all
Lots of potentials here.

Tyres or wheel balance.

Sticking piston/calliper.

Warped discs, although some people claim there is no such thing and that it is uneven carbon build up, rather than warping. Some also say discs need to be honed.

Dodgy ABS kicking in.

Worn suspension part.

As for the lack of braking, is this really the case, or is it just the sensation of lack of braking? If it shakes a lot, then physiologically it can mean you then let off the pedal slightly.

jet_noise

5,645 posts

182 months

Friday 5th July 2013
quotequote all
Dear T,

warped or unevenly worn discs or a build up of pad deposits all do this.
An occasional if regular feature of brakes on Monaros of which I have an example.

Mine vibrated at a particular speed. There was one place on my commute where I braked from 70 on a downhill approach to a roundabout and I had a vibration which started at 65 and disappeared by 55.
In my case it was eventually diagnosed to uneven wear caused by material variations across the surface of the disc.

Pad material build up can be cured by an Italian brake tuneup - several contiguous hard applications from high speed can burn it off.
If it's warped then a skim may fix. It may return. If it does then it's new discs,

regards,
Jet

Big Rod

6,199 posts

216 months

Friday 5th July 2013
quotequote all
Start with the cheap/easy options first.

Have your wheels balanced by a reputable provider. (Pet hate of mine this. there's only one or two places I trust to do the job properly and one of them balances down to 1g weights.) And while they're at it, get them to make sure the wheel runs true. (You could have a Road Force balance done but that can be £15 per wheel!)

Check your suspension/steering components for play and particularly the lower wishbone bushes/balljoints. (Had an Omega that did this and that's what it turned out to be.)

Check your disks for 'blueing'. Even with the best of intentions I've occassionally left my foot on the brake after heavy decelration and that can cause issues with the surface of the disc.

If it's only under braking then it's not likely to be any driveline components causing it otherwise you'd feel it when not braking.

TameRacingDriver

Original Poster:

18,079 posts

272 months

Friday 5th July 2013
quotequote all
300bhp/ton said:
Lots of potentials here.

Tyres or wheel balance.

Sticking piston/calliper.

Warped discs, although some people claim there is no such thing and that it is uneven carbon build up, rather than warping. Some also say discs need to be honed.

Dodgy ABS kicking in.

Worn suspension part.

As for the lack of braking, is this really the case, or is it just the sensation of lack of braking? If it shakes a lot, then physiologically it can mean you then let off the pedal slightly.
I thought if the wheels were off balance, I'd get vibration without braking at certain speeds? As it is, the car is smooth at all times, until you brake, and only then at speed.

Not sure about the ABS kicking in, it doesn't really feel like that.

I guess it's one of those things that could be difficult to track down though?

The brakes are crap anyway, and I was thinking of upgrading the discs and calipers to larger ones, Pumas are famous for crap brakes. The other problem I have with it is lack of bite (weak servo, apparently).

TameRacingDriver

Original Poster:

18,079 posts

272 months

Friday 5th July 2013
quotequote all
Big Rod said:
Start with the cheap/easy options first.

Have your wheels balanced by a reputable provider. (Pet hate of mine this. there's only one or two places I trust to do the job properly and one of them balances down to 1g weights.) And while they're at it, get them to make sure the wheel runs true. (You could have a Road Force balance done but that can be £15 per wheel!)

Check your suspension/steering components for play and particularly the lower wishbone bushes/balljoints. (Had an Omega that did this and that's what it turned out to be.)

Check your disks for 'blueing'. Even with the best of intentions I've occassionally left my foot on the brake after heavy decelration and that can cause issues with the surface of the disc.

If it's only under braking then it's not likely to be any driveline components causing it otherwise you'd feel it when not braking.
That point in bold is interesting, since I am sure there is an advisory for a front ball joint in the last MOT scratchchin

Big Rod

6,199 posts

216 months

Friday 5th July 2013
quotequote all
TameRacingDriver said:
That point in bold is interesting, since I am sure there is an advisory for a front ball joint in the last MOT scratchchin
Hope it helps! smile

Benj1984

173 posts

131 months

Saturday 6th July 2013
quotequote all
Always worth checking the suspension. A worn ball joint could cause this. Is the judder thought the pedal only? Or steering wheel as well?

I would say its most Lilly warped discs. Best replacing them along with the pads. Not worth a skim really for the price of puma discs.

Benj1984

173 posts

131 months

Saturday 6th July 2013
quotequote all
Though, if you can't feel it through the pedal it's unlikely brakes, more likely ball joint or something.

Riley Blue

20,952 posts

226 months

Saturday 6th July 2013
quotequote all
TameRacingDriver said:
That point in bold is interesting, since I am sure there is an advisory for a front ball joint in the last MOT scratchchin
When did you intend to have this fixed? I get advisories sorted immediately after I'm made aware of them.

TameRacingDriver

Original Poster:

18,079 posts

272 months

Saturday 6th July 2013
quotequote all
Riley Blue said:
When did you intend to have this fixed? I get advisories sorted immediately after I'm made aware of them.
It wasn't me who got it MOT'd, I would have done the same.

ETA the judder is through the steering wheel. I'm going to get it sorted asap.

Ozzie Osmond

21,189 posts

246 months

Saturday 6th July 2013
quotequote all
TameRacingDriver said:
ETA the judder is through the steering wheel. I'm going to get it sorted asap.
Best place to start is a garage with a proper rolling road, as used for MOT testing. They can easily see on their brake meter the figures which reflect your judder (if it's the brakes) and identify which disc(s) are causing the problem. They can also inspect the discs for material deposits or run-out.