Massive Shuddering Under Braking

[dave300zx]

hi im new to owning a toyota avenss i have a w reg 2.0 gls ,

i have a problem when i apply the brakes normally i have a huge amount of brake shudder so bad that the steering wheel shakes but under hard braking they are fine no shudder , i have looked at the discs and the pads and they look fine, the guy i bought it off had this relaced at the last mot as they said that the discs were causing the shudder, does anyone have any ideas someone suggested to me it could be abs sensors playing up

any help would be greatly appreciated

[donnyvfr]

hi im new to owning a toyota avenss i have a w reg 2.0 gls ,

i have a problem when i apply the brakes normally i have a huge amount of brake shudder so bad that the steering wheel shakes but under hard braking they are fine no shudder , i have looked at the discs and the pads and they look fine, the guy i bought it off had this relaced at the last mot as they said that the discs were causing the shudder, does anyone have any ideas someone suggested to me it could be abs sensors playing up

any help would be greatly appreciated

just replaced my discs and pads for the same reason and its fine now, MR T wanted over 300 quid for bits, parts king wanted 215 quid, went to my local partco motor factors and got 2 discs, and the pads for 44 quid!!!! No brainer really!!

[Mooly]

Warped discs would be the first suspect and you can't tell by looking, it's the "runout" that needs to be measured.

Can't see it being anything to do with the ABS... and you don't mention the ABS cutting in or warning lights coming on etc.

Another thought... would worn ball joints/linkages cause this problem ?

[Thermal]

... would worn ball joints/linkages cause this problem ?

I would say... that's more likely than warped discs, since there is no shudder when braking hard and the discs were replaced recently.

If the discs were warped, they would always shudder.

Chances are, that the wear on the joints/linkages was caused by previously warped discs...

In any case, there is something wrong and with all respect, I wouldn't trust the engineering skills of a previous owner on a subject like brakes.

Have a close look yourself, or get a mechanic to sort it out.

[B3rtie]

hi im new to owning a toyota avenss i have a w reg 2.0 gls ,

i have a problem when i apply the brakes normally i have a huge amount of brake shudder so bad that the steering wheel shakes but under hard braking they are fine no shudder , i have looked at the discs and the pads and they look fine, the guy i bought it off had this relaced at the last mot as they said that the discs were causing the shudder, does anyone have any ideas someone suggested to me it could be abs sensors playing up

any help would be greatly appreciated

This has happened to my '02 Avensis and I did exactly what everyone else has mentioned was the 'cause' (discs and pads) but with no appreciable change. This also happened some years ago on another make of car - again no appreciable cahnge after changing discs and pads.

My '02 has recently been the subject of replacement suspension parts (front offside of the car) and a four wheel alignment and guess what? The problem has more or less been extensively cured.

My view is that if you are feel ing the shudder through the Pedal it is more likely to be a disc issue whilst through the steering something else. In fact it is more likely (if a brake issue) to be a badly seated pad or wear or muck in the caliper guide pins which cause the shudder under moderate braking since you will not use such great pedal pressure (this was the cause of the problem on my other car).

I would take the caliper apart (if you can) and check for wear - if none clean and grease the pins inside the seals, also carefully re-seat the pads with copper slip before you do anything else costly. If it is a stearing shudder then it could be wear or misalignment of suspension parts.

Robert

[hopemyavensisworks]

It probably has no bearing on your problem but I had severe shaking which worried me greatly. Taking my avensis 99 to a kwik fit center they checked the tyres and found a big bulge in the rh rear . I replced the tyre and the shaking disapeared.http://www.toyotaownersclub.com/forums/public/style_emoticons/default/thumbsup.gif

[cal]

hi im new to owning a toyota avenss i have a w reg 2.0 gls ,

i have a problem when i apply the brakes normally i have a huge amount of brake shudder so bad that the steering wheel shakes but under hard braking they are fine no shudder , i have looked at the discs and the pads and they look fine, the guy i bought it off had this relaced at the last mot as they said that the discs were causing the shudder, does anyone have any ideas someone suggested to me it could be abs sensors playing up

any help would be greatly appreciated

Yes, this problem is a curse for the Avensis since it was first launched. I am pretty certain that the problem you have is due to warped discs.

Warped discs can be cured by either replacing the discs or skimming the discs. However, replacing the discs with another genuine one will only cure the problem for a short while. The problem lies with the hardness of the pads and the quality of the steel. Unfortunately, the quality of steel is not what it used to...

Once I was a high mileage driver and I had to go through couple of discs and pads to cure this annoying problem. Some of the discs including the genuine one had to be replaced within the course of 7000 miles. I will recommend replacing the pads and discs with the following;

* Pads - Apec pads.

* Discs - ADL blueprint discs.

This combination seems to work wonders. Apec pads aren't too expensive but softer pads thus kind to the discs. The only drawback I found was it tends to dust a little more. Nonetheless they are good pads. The ADL blueprint discs are very well made with slightly different design to combat heat.

So, to get to the bottom of this problem, insist on having the above combination. Hope it gets cured soon!

[t-spiritpete]

Warped discs would be the first suspect and you can't tell by looking, it's the "runout" that needs to be measured.

Can't see it being anything to do with the ABS... and you don't mention the ABS cutting in or warning lights coming on etc.

Another thought... would worn ball joints/linkages cause this problem ?

With all due respect it is well documented and proven that brake discs do not warp, it is a myth. Friction material can in certain circumstances can be transferred onto the disc giving the impression that the disc is warped. Changing the discs and pads will give a good result providing you use a different friction pad as stated in a post above by cal.

Regards, Pete.

[Thermal]

With all due respect ...

Sorry, but I have to disagree somewhat....

Warping can be caused by excessive heat.

When the disc's friction area is at a substantially higher temperature than the inner portion (the hub), the thermal expansion of the friction area is greater than the inner portion and warping occurs.

Another possible cause of warping is when a disc is overheated and the car is stopped with the brakes continuously applied.

In such a case, the area where the pads are in contact with the disc will cause uneven cooling, which can lead to warping.

Also, incorrect fitting can also lead to warping.

The disc's retaining bolts must be tightened progressively and evenly.

The use of an air gun here is a complete NONO.

A workshop manual must be consulted to see the proper pattern for tightening as well as the torque values for the bolts.

Wheel nuts must never be tightened in a circle, and tightening should be done with a torque wrench.

However, not all brake pedal pulsation or steering wheel shaking is due to warped discs.

Brake pads that are operating outside their designed temperature range can leave a thicker than normal deposit in one area of the disc surface (glazing), creating run-out that will grab with every revolution of the disc.

Over time, pulsation and shuddering becomes worse, and lead to excessive wear on suspension parts and joints.

Hope this helps...

[dave300zx]

thanks to everyone for there replys i havent been using the car much so im just getting around to trying to fix it now , i spoke to the previous owner who has told me he has had several replacement discs in the time he owned the car , so im going to go and buy some today and see if this cures my problem the car is also close to mot time so keep your fingers crossed

[georgepg]

hi all i have an avencis 1800 x reg that also as a light shaking on my steering wheel when braking but not excessive it seems to happen when i break hard but if i put gentle pressure on the brakes instead of using an elephants foot no signs of shaking, its a mystery,even when breaking hard i have stopped slamming my foot down, and now use gentle but firm pressure and it seems to do the trick, could it be something to do with the actual breaking system of the avencis model. My local garage could find no wear and tear on either the pads or the shoes and i even had the steering colum checked out ok its a mystery

[B3rtie]

Warped discs would be the first suspect and you can't tell by looking, it's the "runout" that needs to be measured.

Can't see it being anything to do with the ABS... and you don't mention the ABS cutting in or warning lights coming on etc.

Another thought... would worn ball joints/linkages cause this problem ?

With all due respect it is well documented and proven that brake discs do not warp, it is a myth. Friction material can in certain circumstances can be transferred onto the disc giving the impression that the disc is warped. Changing the discs and pads will give a good result providing you use a different friction pad as stated in a post above by cal.

Regards, Pete.

I agree with Pete - gas expansion between the pad and disc during braking can also casuse this problem.

How hot do you think a piece of thick steel has to get before it bends?

PS have the brakes been belead properly? Air in the fluid is also a possibility.