craig1410
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| posted on 16/4/17 at 03:14 PM |
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Help isolate droning noise on Mazda 2 pls?
Hi,
My daughter has a 2013 Mazda 2 with about 52k miles on the clock (owned from new). It's been well maintained but has, over the last few months,
developed a quite noticeable droning noise and vibration which can be heard at 30/40 MPH city speeds but seems to peak at just over 60MPH. The noise
is road speed dependent and doesn't change if the clutch is depressed while at speed. It also doesn't seem to be affected by the hand or
foot brakes to any noticeable degree nor to slight variations in steering angle.
I'm pretty sure the noise and accompanying slight vibration are coming from the front and my son said he could feel the vibration through the
passenger's footwell. I'm pretty sure I could feel something too through the footwell on the driver's side and maybe even through
the accelerator pedal although I'm not certain of that. The steering wheel feels vibration free so and the car had two new front tyres not long
ago (but after the vibration started to develop) and the tracking was set at that time as there was some wear on the inside shoulders.
I replaced the brake fluid recently and when I had the wheels in the air I checked for any obvious signs of wheel bearing wear but the wheels were
spinning smoothly with no obvious play at either 12/6 o'clock or 9/3 o'clock.
You guys know that these sorts of things are tough to track down sometimes so just thought I'd ask here in case this is a common problem on the
Mazda 2. My gut tells me it might be the inner CV joint but I'm going to also check the outers because I did notice what sounded like a rubbing
noise on full lock in either direction. It actually sounded like the tyre hitting the bodywork but it's a standard car with standard wheels and
tyres so I can't understand why that would be happening. There was no sign of "catching' of clacking on full lock so not conclusive
of outer CV failure IMO. I'll check there that noise is coming from when I get the front off the ground.
I'm just off to have my Sunday dinner before getting into the overalls to have a look so if anyone has any good tricks to isolate which
component is failing then please let me know.
Thanks,
Craig.
ps. Happy Easter to all whether that means religion or just chocolate to you! 
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ian locostzx9rc2
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| posted on 16/4/17 at 03:47 PM |
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Check for deformed tyre or wheel bearing does the noise change whilst cornering loading the bearings. Have you also checked the rears aswell .
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craig1410
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| posted on 16/4/17 at 04:04 PM |
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quote:
Originally posted by ian locostzx9rc2
Check for deformed tyre or wheel bearing does the noise change whilst cornering loading the bearings. Have you also checked the rears aswell .
Pretty sure the tyres are okay as they were renewed after the noise started and this didn't change the sound. Also, as I mentioned, it
doesn't change when doing a slight "slalom" on the road. I looked at the rears when I changed the brake fluid and they seemed fine
but obviously I'll check them again if I can't find anything on the fronts.
Heading out in the rain now to take a look under the car. No chocolate eggs for me until I find the cause...
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perksy
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| posted on 16/4/17 at 04:18 PM |
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Slightly' bent' Driveshaft ?
Also Jack the front end up and turn the wheels by hand, check for and 'rough' feeling etc
Gearbox & Diff oil level checked and/or correct grade used ?
Double check the wheel bearings and CV joints
They had a callback iirc for wheel bearings around 2008, but that was for Rear wheel bearings..
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Russell
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| posted on 16/4/17 at 04:23 PM |
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Exactly the same symptoms you describe on a 2002 VW Polo turned out to be the nearside inner CV joint. It was only after I took the shaft off that I
could feel the slightest play in the joint.
I'm a bilingual illiterate. I can't read in two languages.
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craig1410
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| posted on 16/4/17 at 04:53 PM |
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Thanks for the feedback guys.
Just had a look and as usual there is no smoking gun but a few observations:
1. I used a set of vice grips to isolate the outer CV joints and they seems fine with minimal slop (1/4" of tyre circumference roughly) and no
feeling of roughness when spinning the wheels by hand with both off ground.
2. The offside driveshaft is a 2 piece affair with an intermediate joint and again, if I isolate the joint by clamping between gearbox and
intermediate joint, there is still minimal slop although I can hear and feel a little bit of a clunk in this joint as I rock it back and forth.
3. Wheel bearings (from anyway) feel and sound fine as far as I can tell.
4. The rubbers on the outer CV joints make quite a bit of rubber-squeak as they are rotated on full lock but there are no signs of splits or leaks so
I guess this is normal.
5. There is a bit of slack in the gearbox if I rock one wheel and observer the other one. I've got the car in 1st gear to stop the engine moving
when I do this so this is pure drive line slack. Not sure how much is 'normal' here but there's a good few inches of tyre
circumference when rocking back and forwards.
6. Lastly, the lower engine mount seems to be very soft and is moving quite a bit even when just rocking wheels back and forwards by hand. The mount
is the type with a large end and a small end, a bit like an engine conrod, and it's the large end which has a lot of play in it. I'm going
to do a bit of googling on that now and see if it is a common issue. If the mount is cheap then I might just get one for it as an elimination step.
That said, I can't imaging this would cause a "droning" noise as the oscillation frequency would be too low for the whole engine.
But you never know, it might be allowing some other vibration source to resonate or something.
If any of the above triggers any other thoughts then please let me know.
Cheers,
Craig.
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perksy
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| posted on 16/4/17 at 06:37 PM |
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Just adding to my previous post
Had a look regarding call backs and this year Mazda 2 and it had a Steering Callback: No R/2016/143
"The lower nut & bolt securing the front shock absorber to the steering knuckle on either side of the affected vehicles may not have been
tightened to specification. The bolt may work loose, causing a rattling sound, and could fall out."
Hmmm Engine mount, there's a thought ?
These cars share quite a few bits with the same year Ford Fiesta's so worth a cross reference if you can ?
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craig1410
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| posted on 16/4/17 at 07:10 PM |
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Thanks, I'll check those shock absorber mounts although the car was under dealer servicing for the first 3 years so hopefully they will have
dealt with that, assuming the recall came up during that time.
Yeah I was also searching for Fiesta related issues but the engines are completely different as far as I am aware so there is a good chance the
mountings won't be common parts.
I noticed while under the car that both front wheel rims have signs of pothole damage to the inside bead so I took the wheels off and measured it and
it's about 3mm different across the site of the impact versus 90 degrees out of phase. To be honest, while not ideal, I have seen wheels farther
out of true without causing any issues so I'm not convinced this is the problem. I would also expect this to cause a lower frequency vibration
akin to an out of balance wheel and not a droning sound. But anyway, I switched the wheels from back to front axles and took it out for a drive. The
droning sound is still there but (I think) sounds a bit different. Of course that could just be a resonance difference caused by the 4mm difference in
tread depth or maybe the wheel buckle is causing it. I don't know.
I'm tempted to get a dog-bone mount for the rear of the engine as these are cheap and easy to fit and should firm things up a bit regardless if
this is the cause. If I was finding the noise was worse under high torque demand or on over-run then I'd be more inclined to blame the dog-bone
mount but it's not...
Maybe I should run several lengths of rubber tubing to each location (CV, wheel bearing, inner CV) and use them like stethoscopes while sitting in the
passenger's seat! See which is loudest!
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Mr Whippy
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| posted on 17/4/17 at 12:16 PM |
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chuck the spare on each wheel at a time and see if the noise is still there if it is then it must be the brakes or driveshafts. Could be a bulge in
the tire from a pot hole or even a buckled wheel, seen loads of those
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craig1410
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| posted on 17/4/17 at 12:27 PM |
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Just a brief update.
I know this was suggested earlier but I was more focussed on the fronts due to that being the apparent direction of the sound/vibration but having had
a closer look at the rears (now on the front), they are showing the typical "sawtooth" wear pattern on the outer tread blocks. These tyres
are original Toyo Proxes R31s which have now covered 52k miles but still have 4.5mm of tread and having been on the rear all that time it's not
uncommon to see this wear pattern.
As I said in my last post, I swapped from front to back but what I did this morning was also swap from left to right on the front to reverse the
direction of what used to be the rear tyres but now on the front.
Having done a quick test drive the noise is still there but again it sounds different, perhaps a bit softer in tone, so I think it's worth
running this for a couple of weeks or so to see if the wear evens up a bit. If not then at least running on the front will wear them down faster and
we can look to get a new pair of tyres in a month or two. If we do that then we'll get the rims trued at the same time.
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craig1410
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| posted on 17/4/17 at 12:28 PM |
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quote:
Originally posted by Mr Whippy
chuck the spare on each wheel at a time and see if the noise is still there if it is then it must be the brakes or driveshafts. Could be a bulge in
the tire from a pot hole or even a buckled wheel, seen loads of those
Unfortunately there is no spare on this car. That has caused considerable hassle in the past when my wife used to use the car and had 3 pothole
"incidents" within a few months! 
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Schrodinger
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| posted on 17/4/17 at 05:16 PM |
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I was lead to understand that a saw toothed pattern on tyres was caused by a damper passed it's sell by date. Might be worth checking them out.
Keith
Aviemore
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ian locostzx9rc2
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| posted on 17/4/17 at 06:32 PM |
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If you have got thread blocking saw pattern on the tread that will be the noise if the tyres are that old aswell I would change them as the tread will
be hard .
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ian locostzx9rc2
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| posted on 17/4/17 at 06:33 PM |
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Saw pattern can be caused by worn dampers .
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craig1410
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| posted on 17/4/17 at 08:17 PM |
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Hi,
Yeah I know sawtooth can be caused by faulty dampers but that normally shows a different shape to what I'm seeing here. With these tyres, it is
every single tread block on the shoulder which is affected and that is typically caused simply by the fact the rear is only ever deforming the tread
blocks laterally or in a single direction longitudinally. This is what causes the little ramps to appear as I understand it. If it was damper issues
then it would tend to make the entire tyre look a bit more like a 50p piece rather than being limited to each tread block.
I agree these tyres need to be replaced soon but I'm not quite ready to throw them out yet, especially as we just replaced the other axle. They
will be replaced before the winter one way or the other though. Just hoping we can get a few more miles out of them first. I don't think
I've ever had tyres needing replaced before they are actually worn out before!
[Edited on 17/4/2017 by craig1410]
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skippad
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| posted on 18/4/17 at 07:31 AM |
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I had same problem on my wifes Citroen C1...
Checked everything, bearings, brakes, even changed gearbox.
I swapped some wheels off my sons Lupo.... hey presto... no noise!
I could'nt believe tyres (Sunnys) could effect car that much!
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craig1410
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| posted on 18/4/17 at 09:18 AM |
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Yeah I know what you mean, it's one of those things you've really got to experience first hand before you believe it. I had this a good
few years ago on a SEAT Leon Cupra Mk 1 so I know it can happen but it still takes you a bit of time ruling everything else out before you accept it.
Like you say, it's surprising that a rubber donut full of air can make such a noise.
Then again, try cycling a mountain bike with knobbly tyres on the road! Rrrrrr..rrrr.rrrr.rrrr 
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