Steering wheel vibration under hard braking(LCR), help?

[Mark300zx]

Hi,

the car has had new front discs fitted by the previous owner but under hard braking the the steering wheel vibrates!

I haven't checked the discs for run out yet but wondered if there is anything else I should be locking at?

Mark

 

[lordgibbness]

This can be caused with new discs during the bedding-in process if the driver was using an on-off-on-off braking technique or braking too hard and stopping for too long, which leaves brake pad material un-uniformly across the surface. You can get them skimmed and do the correct smooth braking bedding-in process (or get them replaced under warranty if they're new).

 

[Mark300zx]

Thanks for the reply, posted up again for anyone searching, I think I have cured it, the previous owner had the tyre pressures at 28 psi and have put them up to 35 psi and the vibration has gone

 

[lordgibbness]

The recommended tyre pressure is 33psi, but if 35 works for you...

 

[mike2926]

is that 33 all round?

 

[lordgibbness]

Yeah - for the LCR at least. Don't trust petrol station guages etc. though - get yourself a proper tyre pressure guage.

 

[mike2926]

i will, i must admit that i havnt checked my T P in a while..... ill do that today

 

[Mark300zx]

Read a few posts and some people say 33,34,35 and thanks it was done on a proper gauge

 

[lordgibbness]

Yeah you can always go a few psi either side to get the handling characteristics you prefer

 

[ibizacupra]

tyre pressures and braking vibration?

thats a new one on me

 

[lordgibbness]

Well, I wasn't gonna say anything as he seemed happy!

 

[Mark300zx]

Well, I wasn't gonna say anything as he seemed happy!

Please feel free to bestow me with your wisdom?

 

[lordgibbness]

Please feel free to bestow me with your wisdom?

You said your brake juddering problem went away when you upped the pressure so I didn't comment on it, even if it sounds a little suspect...

 

[Mark300zx]

You said your brake juddering problem went away when you upped the pressure so I didn't comment on it, even if it sounds a little suspect...

Please expand upon your thoughts?

 

[lordgibbness]

Brake judder is usually an issue with the discs or hubs: runout, warping or un-even brake pad distributed across the disc. If your issue was with brake juddering it's the first time I've heard of tyre pressures being the cause. Tyre pressures are usually something you'd alter for changing handling characteristics.

 

[Fl@pper]

tyre pressures and braking vibration?

thats a new one on me

i have felt a bit of swerve/wobble when one has dropped lower than the other in the past

 

[Damoegan]

Vibration throught the steering wheel under braking is normaly warped discs.

 

[Mark300zx]

i have felt a bit of swerve/wobble when one has dropped lower than the other in the past

Which is what I was thinking, do the esp/abs adjust braking at all?

 

[traumapat]

Which is what I was thinking, do the esp/abs adjust braking at all?

the dash lights should flash if abs/esp gets involved... but yes it would judder as the brakes pump. pedal will go straight to floor too so id think youd notice.

pads ok? id say uneven wear or warped. not thats happened to me though.