Vibration when braking

Zascar

I have a 96 Civic 1.5VTi, and lately I have noticed that when I am going pretty quickly, say 80, whenever I brake the car vibrates/shudders when going roughly between 75 and 65. I can really feel it through the steering wheel. I know that I need my tracking done, as I have a slight steer to the right, but I was told this could be somehting different. Warped Brake disks, or nackered suspension were 2 suggestions...

Anyone any ideas on this?

Cheers,
Zascar

mike65

Sounds like your disks are shot, nah that judder only shows itself under braking. I'd say your tracking is all adrift, simple job at your local Advance tyre place,
it takes about 20 mins and costs about 30 euro. That should make some difference to your wheel wander.
Oh yeah, get your wheels balanced while your there, might as well make a morning of it...

Mike.

Quigs Snr

As Mike says get your car tracked. My old MG was vibrating through the steering wheel above 50mph, turns out the wheels needed balancing. Also when you hit the brakes the car practically did a 90 degree turn left and leapt over the ditch (a combo of a slightly down tyre on one side and also tracking - thankfully not the more expensive disks).

Zascar

Cheers Lads, What exactly is the difference between balancing and tracking? I know what they do when they balance your wheels, but what do they do with tracking?

mike65

Tracking is a black art they NEVER tell you what it involves!

I hav'nt a good idea myself but I found this -

http://www.beardmorebros.co.uk/website%20pages/how%20to/tracking.htm

Mike.

the evil belly

if memory serves it involves adjusting the camber of the wheels to make them run true and so that the rear wheels follow correctly when steering. involves the use of some lazer thingy

ozpass

Nah....

Tracking is also sometimes called tow-in / tow out. It's the angle of the front wheels compared to the central axis of the car. One wheel towing out and one straight will cause the car to pull in that direction under extreme acceleration / deceleration.

Make sure they do it properly by adjusting both steering tracking arms and not just one. You'll know this by making sure the car drives dead straight when the steering wheel is in the dead-straight position.

It could also be a warped brake disc. The warping in the disc is extremely small (hence no vibration under normal conditions) but when the caliper grips, it creates a cyclical increase in pressure against the pad which causes the entire caliper to judder, hence the vibration.

Ironically the additional heat generated over a small portion of the disc makes it progressively more warped, and progressively worse.

Get it fixed sooner rather than later.

chernobyl

Antilock braking system?

mike65

Originally posted by ozpass
[B

It could also be a warped brake disc. The warping in the disc is extremely small (hence no vibration under normal conditions) but when the caliper grips, it creates a cyclical increase in pressure against the pad which causes the entire caliper to judder, hence the vibration.

Ironically the additional heat generated over a small portion of the disc makes it progressively more warped, and progressively worse.

Get it fixed sooner rather than later. [/B]

I had a failed calliper on an old Corsa, after about 5 miles it would heat up and judder would appear, I'd go through a puddle and it would lessen.
That said the judder was at all speeds not just at
high speed, or under braking

Mike.

louie

The only thing you need to do is change the brake disc & brake pads also. that usually happens when the brake disc are oval.
tracking will shake your SWheel are high speed, and a bad balance on your wheels will shake the entire car.
that's the difference.

Hellrazer

If you get a wobble at say 60-70 that goes out of the car at say 80 then its definately a wheel balance problem-one of the weights used has probably fallen off.Warped discs only show at braking.Suspension problems show on rough roads.A pull to the left can be quite normal as most roads slope to the left to allow water run-off.
A pull to the right is bad tracking.
Hope this helps.
Richie.

Chimaera

A pull to the left can be quite normal as most roads slope to the left to allow water run-off.

I think they actually set the tracking to compensate for this somewhat, so that the car will run straight on a normally cambered road.

Hellrazer

Originally posted by Chimaera
I think they actually set the tracking to compensate for this somewhat, so that the car will run straight on a normally cambered road.

Some manufacturers do---but the problem with this is that on a non-cambered(totally flat) road the car will pull to the right which can be quite dangerous.