Hi All,

I have a vibration you can feel through the steering wheel and seat when braking from 50 and higher. It obviously gets worse the faster your braking from.

I have just fitted new front discs and pads and had new rear callipers fitted just over a year ago

No wheels are dragging so I don't suspect a sticking brake piston.

Just positing as interested in hearing from any other members who have had a similar issue and discovered it was something ither than front discs/pads.

Thanks 2012 4.4 TDV8 Vogue Santorini black ivory leather

Warped disks or uneven pad deposits are the usual culprits made worse by worn suspension bushings BUT they can easily be warped by over torquing wheel nuts or doing them in the wrong sequence. Try loosening and retorquing. 2012 TDV8 Vogue (L322)

Thanks, the front discs and pads were fitted today. I cleaned and wire brushed all mating surfaces to ensure a correct and true fit of the discs. I will check the rear discs and pads.

Out of interest which suspension parts when worn would contribute the most to a vibration when braking? 2012 4.4 TDV8 Vogue Santorini black ivory leather

Don’t waste time with checking the rears. Upper and lower control arms and their bushings. Wheel nut torque is more crucial than people think due to the design of the hub to disk interface - you did use a torque wrench? 2012 TDV8 Vogue (L322)

Yes I used and have always used a torque wrench for the wheel nuts. I think this was 100 NM's or maybe 120.

Thanks for the advice RE the rears, I knew I was clutching at straws looking there.

Are control arm replacements something a inexperienced home mechanic could replace? 2012 4.4 TDV8 Vogue Santorini black ivory leather

I would look at the trackrod ends first before diving deeper.
I think the wheel nuts should be 140nm.

Thanks, this is why I love car forums, great members. 2012 4.4 TDV8 Vogue Santorini black ivory leather

The control arms can be a struggle due to the ball joint taper fit seizing with rust. Plenty of info on here and on YouTube showing what’s involved. Outer track rod ends are easy to replace but the inners can also have play which is a much more involved job. Mine still slightly judders and I put it down to last time I had new tyres and they did up the nuts with an impact driver which permanently warped the disks or hubs. When I re torqued them I needed all my strength with a breaker bar to loosen them. 140nm doesn’t take much physical effort to reach. 2012 TDV8 Vogue (L322)

and nuts torqued in a certain way - not just one after the other

Click image to enlarge

How would I check if my hubs are distorted due to a past owner/garage incorrectly tightening the wheel nuts? Would a straight edge steel be adequate or used there a better way to test?

I have owned the car for over 3 years and the vibration has only recently manifested itself and it's quickly got worse. The discs and pads fitted are top quality and have been on since I purchased the car.

The suspension components at the front are quite rusty but there are no knocks, rattles, clonks or other noises. 2012 4.4 TDV8 Vogue Santorini black ivory leather

And when torquing wheel nuts, you keep going round them until the torque wrench clicks without the bolt turning anymore. 3 times is usually enough.

Worn bushes/joints can also cause it, the loads shift as dynamics change. Does it pull if you floor it then suddenly let off the throttle? Usually a sign of suspension/steering issues. Could even simply be tracking....

The only real way to check for disk and hub runout is to use an engineers dial test indicator mounted on an arm and magnetic base and reference the tolerances in the workshop manual. Again there are YouTube videos detailing this procedure. A more common reason for brake judder often mistaken for warped disks is uneven pad deposits caused by holding the brakes on hot disks at a standstill. The cure for this is to do repeated high speed hard braking without stopping to recondition the disk surface. 2012 TDV8 Vogue (L322)

The car pulls dead straight when accelerating and braking, also no noises.

The best way to describe the issue is low level high frequency vibration felt through the brake pedal and seats when braking from speeds above 50 mph.

As I have changed discs and pads with no change I have ruled out front discs and pads. I recently changed all the wheel bolts as some had started to swell. I believe the upper and lower arms are original as are the track rod ends. It has a new lemforder ARB but the garage only did one side as the other was OK.

I know I could take it to the garage but I am trying to do as much as I can myself. 2012 4.4 TDV8 Vogue Santorini black ivory leather

High frequency doesn’t sound like normal brake judder as this is usually low frequency pulsing / once per wheel revolution. Have you been around the wheels touching them after a drive to see if any are very hot as this now sounds more like a stuck caliper. 2012 TDV8 Vogue (L322)

Hi, you might also consider front tyres, bushes & bearings in that order if your comfortable it's not the discs themselves, firstly check for any wear in the fronts and the steering linkage, i.e. is there any excess play.

It could be the original discs had distorted with the hubs due to some previous trauma but remained aligned, as in 2 wrongs make a right, when you changed the discs it's created a misalignment. I've seen this a few times before. You can check disc runout with securing the disc via the wheel nuts directly and rotating with a scriber clamped just touching the disc surface. As you spin the rotor does the scriber scrape the disc consistantly all the way round ? Plenty of vids on Youtube to show how.

You can also use the same method to check for tyre roundness.

Tyres can warp for any number of reasons and they do develop flatspots or sawtooth that may not become apparent until you put extra load on them by braking and thus the mass starts to move onto the front axle and loading it up.

Try replacing the tyres to the rear, manipulating the pressures etc. and maybe get them rebalanced and ask the technician to check for flat spots, ovalling etc.

Andy Fuji White / Jet 2012 4.4 TDV8 Westminster