406oc.co.uk

....and not caused by the usual suspects. This has been a problem with the car since I got it over a year ago. Lots of new parts fitted since and it's still there, genuine OE discs, new pads, lower arms, ball joints, drop links and track rods. When I brake from a speed over 60mph I get rattle/vibration through the steering wheel (but not through the brake pedal). The car pulls up in a straight line, no braking issues. I can occasionally feel the same rattle going over speed bumps etc. My thoughts are that there is something amiss in the steering rack or column. Does anyone have experience of such an issue?

Have you checked the steering rack mounting bolts for tightness?

Check the steering column and rack universal joints bolts for tightness and wear in the joints.

i was thinking the same thing,that steering rack

Thanks Jasper, I finally got round to taking a look tonight. The rack mounting bolts are correctly torqued. Access to the column is very poor, but the lower bolt and joint looked fine to me (part 5). I assume access to the upper bolt can be had by removing the plastic cover from underneath the steering wheel?

Which upper bolt do you mean?

Am having the same issue when braking.. Especially on the left side.. I changed disc, pads bearing hub, braking caliper all original .. But the vibration will go, after a week it will come back.. Please what can I do next

NinoB wrote: ↑Thu Mar 04, 2021 11:00 pm I changed disc, pads bearing hub, braking caliper all original

I'm not entirely sure which parts you have changed there and which you're saying are original. The usual suspects are brake disk, hub, tyre, wheel, suspension components. Ooh, brake pads too apparently. Although of these I don't think wheel/tyre will go away and come back. Perhaps you could get each corner in the air and check then for any binding etc. and check the suspension components. Left side, front or rear? I'm not sure it's safe to say it's coming from one side or the other either, things have a way of transferring across the car, especially vibration. Don't assume the new brake disk is perfect either.

I have changed brake disc, entire hub, brake pads, brake caliper, (change pad and disc almost 3 times).. And all items are original and new,
But i didn't change ball joint and steering rack control arm.. Because i checked and saw that they were firmly ok.. So can these two cause the vibration..?

Oh I see, I thought by original you meant original to the car, not OEM. I think if you changed the disk then you've removed that from the equation, er, several times Did you change them both sides? It's hard for me to tel from here, maybe the vibration is so bad it's unmistakably coming from the left front, but I don't think you can discount it coming from somewhere else as vibrations can transfer across the steering. Up in the air with it, examine everything with a pry bar.

Yes i change both sides twice.. Then everything will be but after few days the vibration comes back at any speed above 70km/hr.. The 1st two disc that i changed the discs wrapped out(only left side) while the right side is ok.. So that's why am blaming the left side.. So now am thinking to disable the abs block and try driving with out abs and see it the vibration might be gone.. What do you suggest?

NinoB wrote: ↑Tue Mar 09, 2021 9:56 pmwrapped

I think that's "warped" that's been auto corrected. New hub, new caliper, new disk twice. I don't like the idea that the new disk warped so soon, new hub eliminates rust there, new caliper eliminates stuck caliper overheating the disk. Maybe the master cylinder? Collapsed brake line? Does the disk get noticeably hotter that side than the other?

Oh yes, as far as I remember a duff reluctor ring only gives trouble at low speed but... It's worth trying it just to eliminate it.

I had a front wheel vibration problem following disk replacement with a different car years ago. After all sorts of attempts to cure it I gave up having no money to do anything else. A few months of gentle braking later I realised the vibration had gone no matter how you used the brakes.

Another thing I noticed over the years is that 406's are sensitive to wheel imbalance front and rear. It can be worth swapping your spare for each of the other 4 wheels in turn to absolutely rule out balance and tyre bulges/uneven wear. Takes a bit of time/effort but costs nothing.

i even swapped left to right front tires, still no difference, so this morning i remove the wires from ABS block and drive the car like that, what even surprised me was no difference with or without the ABS, was just testing and see it ABS might contributed....still front right wheel vibrates on braking..this is frustrating..omg

Hi NinoB
Earlier you said that the vibration was on the left side, now after swapping tyres over you have vibration on the right. Suggests either tyres or a wheel issue.
Also you say problem is over 70km/hr, I'd suspect an out of balance tyre or out of round.
Have you tried putting the rear tyres on the front?
Andy

No.. The vibration is still on left after swapping .. No changes.. But i never tried swapping back tyres to front..