Low gunting noise on stop and start

[Roystond]

Toyota Avensis  S240WCA  First Registration 29-1-99

Owned since 26-6 2001  i.e.  Approx 18 (great) years

Grunting noise 

This is an automatic car I have owned for 18 years and it has been absolutely superb all that time and any problems easily fixed. It is very quiet to drive and auto change of gears almost undetectable. BUT I had new disks and pads in January and since then I have had a grunting noise (hard to describe) which occurs when waiting in drive and then starting off, only occurring at that time or when coming to a stop and as you approach stop and remaining in drive (D)  as you stop (using foot brake or sitting in drive but stationary held by footbrake then moving off. It only occurs round these two points It is non metallic. It sounds to me like rubber on metal but maybe that is misleading. In all the years i have had the car IT HAS ONLY OCCURRED SINCE THE CHANGED OF PADS AND DISKS.

I have had the garage who fitted the pads etc check it over and dust it and they found no fault.  In desperation I went back to a previous garage I have used successfully for 7 or 8 years and asked them to check everything including lubrication and they found no fault but it still occurred. This previous garage is owned and run by a Toyota trained owner who specialises Toyota but does deal with all makes. It is one in which I have absolute confidence.

I am aware that if the car is stationary but with the engine running and is in drive there is creep and if you keep it stationary the pads are in contact with disks which are trying to spin and it sounds to me as if it is the pads coming free of the disks but not instantly which is one reason I asked for the lubrication to be checked.

I can create the noise by sitting in the car, engine running, and putting it in drive (some noise occurs) then still stationary putting it in reverse (noise occurs). It does not occur in normal driving only when you come to a standstill or move off and of course it is a bit intermittent.

It has occurred to me that as the pads and disks were after-market parts I could replace with genuine Toyota pads. But this is just speculation. (I have found in the past that an after-market exhaust was very noisy but when replaced by a genuine Toyota exhaust it was completely quiet again.) 

I have recorded it and this has almost captured the sound. An mp3 sound file is attached which almost captures the sound. Any metallic sound on the recording are just the sound of me moving the gear selector to drive from reverse or reverse to drive.I am not sure whether the forum accepts sound files but i have tried it.

Any ideas suggestions would be welcome.car 1 accoustica.mp3car 1 accoustica.mp3car 1 accoustica.mp3car 1 accoustica.mp3

Roystond

 

[Mike169]

Hi Alfred, I think you have answered your own question.

After market parts are inferior as a rule and I really believe if you had fitted genuine Toyota parts you would not of had this noise.

Aftermarket parts, in this case disc pads are often too hard and this causes problems and I also think if when your old brakes were fitted you'd stop in a certain distance over a measure of yards/metres but I feel the pads you have fitted will take a few metres/yards longer to stop your vehicle. 

Now it's your choice my friend, either put up with the noisy brakes or change the pads for genuine Toyota ones and hope that cures it but if it doesn't, which is unlikely you may have to change the discs for genuine ones as well.

All the best, Mike.

[TonyHSD]

Hi, that is absolutely normal noise and can happen with original Toyota parts too. You just had not applied enough pressure on the brakes to hold the car stationary or when braking just push it harder , I can replicate those noises anytime I want, even with brand new car with original brake pads and discs. And if the car been checked already no need to worry just drive  it as is. Sometimes aftermarket parts especially with brake systems can be much better than original equipment, all depends what had been installed. 

Regards 

[mrfixer]

What you have there is known in the industry as 'creep-groan'. Its a low-frequency high-intensity self-excited oscillation of the pad-disc system. Its due to stick-slip between the pad and disc and depends on the pad/disc characteristics. It is a very common phenomenon and not a defect. You may find that as the pads bed-in and glaze slightly the noise will diminish. Don't worry about it.

[Roystond]

Thank you for your helpful replies. After  reading them I decided to consider replacing first the pads and then if necessary the disks with "Genuine Toyota parts". I approached my local garage to get quotes but they told me that there are no genuine Toyota pads. This supply has been over taken by the main suppliers like Girling. Although they sell "Genuine Toyota parts "(and may have Toyota stamped on them) they don't come from Toyota so even if my garage supplied new parts they would no be any different.  Is this correct? Has anyone background information on this?

Thanks

Alfred

[Levon]

Hi Roystond

Off topic a bit, but- have you ever had a change of ATF fluid in the 18 years?

Thank you.

[Konrad C]

I had this brake problem when I own my '98 1.8 Avensis years back. I put it down to brake dust, because when I washed the car, I aim the hose at the brakes, and the water ran out black. Then for a while the brakes were quiet. 

To confirm the issue, when I was slowing and nearly stopped, the brakes would suddenly sound like a huge bass speaker! The speed was below 15 mph. 

In my case I eventually changed the discs and pads. 

I did change the brakes to Blueprint brand, but they developed warp feel after a few months! 

Since I now have a later Mk3 Avensis, I have never had that problem, but have rear pads that stick to the discs if not driven after washing the car. The pads stick to the rusty discs. Once used, all is fine.

Try spraying brake cleaner onto the brake pads, to dislodge the dust. Failing that, take the pads off and clean them. Hopefully this will save you changing the brakes early. 

[mrfixer]

14 hours ago, Roystond said:

Thank you for your helpful replies. After  reading them I decided to consider replacing first the pads and then if necessary the disks with "Genuine Toyota parts". I approached my local garage to get quotes but they told me that there are no genuine Toyota pads. This supply has been over taken by the main suppliers like Girling. Although they sell "Genuine Toyota parts "(and may have Toyota stamped on them) they don't come from Toyota so even if my garage supplied new parts they would no be any different.  Is this correct? Has anyone background information on this?

Thanks

Alfred

Toyota have never made their own pads. Car manufacturers source their braking systems from braking specialist companies such as Akebono, Lucas TRW etc.   Pads are sourced from friction product suppliers such as TMD (whose brands include Textar, Pagid, Don, Mintex).

Read my previous post above and allow your new brakes to bed in. Brake noise may be reduced somewhat by having your garage smear a little Ceratec brake grease on the back of the pads to damp brake vibration.

[Roystond]

Thanks all.