My 2012 Mazda 3 has been making some not-so-great noises lately. It is a 2012 with the 2.5L and 6-speed manual. It has about 185k on it with the original clutch.
When you drive it, starting at low speed, you can hear a noise that almost sounds like a baseball card in the spokes of a bike wheel. This noise is independent of the clutch operation, and most prevalent inside the car. As you drive faster, the noise increases in pitch, and at highway speeds, it is a high-pitched squeal. The car drives like it always has, and it doesn't affect drivability at all. The curious part: if you touch the shifter while in gear (move it side to side, pull it back slightly while in gear, etc) the noise gets louder. Also, the noise is much louder when I have my winter tires on.
At first, I thought it was another bad mount. I already replaced the transmission mount, and both the rear pitch mount and passenger side motor mount. Last gear oil change was around 135k miles, and I have more fluid on order, slightly heavier this time (I read a thread on a Mazda forum that a fluid change solved a similar problem). Wheel bearings could be a possibility, but why would touching the shifter affect a wheel bearing noise? Worst case scenario is that it's internal. I don't want that. Maybe an input/output shaft bearing? I have no idea.
Any thoughts? I thought maybe buying a spare tranny would be a cheap fix, but the cheapest one I can find that's not broken is $700, plus all the clutch stuff puts me well over a grand. Having a shop go through it will definitely cost more than the car is worth. I'd rather trade it in on something else if that's the case before it gets worse.
No takers, huh?
Well, here's a video anyway. Noise gets louder in 4th, 5th, and 6th.
Ever heard anything like that before?
Does it happen when coasting in and or out of gear?
Does it happen in reverse?
Does applying the brakes change it?
In reply to CyberEric :
It makes the noise in all gears, and is speed dependent. Clutch can be in or out and it makes no difference; if the wheels are spinning, it's making the noise. Doesn't seem to make noise in reverse, and brakes don't change it. It makes more noise in the higher gears.
I don't think it's wheel bearings, since it does this with the wheels off the ground and everything feels tight. Maybe an output shaft bearing?
I haven't heard anything like that before. When accelerating, do you get the feeling of the car pulling to one side or the other?
In reply to dj06482 :
Car drives 100% normal. No pulling or any issues. Has a slight vibration on the highway at higher speeds, but it's been doing that for years.
In reply to Tony Sestito :
Listening to the vid & re-reading your post a couple times, if you pushed the clutch in while the wheels are spinning, the noise is unchanged?
If so, here's an idea: with it on jack stands like in the vid, get the wheels spun up to at least 30-40mph and shut the engine off, then get out & see if you can hear anything better through the wheel wells or underneath the car.
Lastly, with the car off, in the air, and in gear, see if you can turn the wheels by hand fast enough to hear/feel what's going on.
In reply to Pete Gossett (Forum Supporter) :
Noise happens when you put it in gear and the wheels start spinning. It does it in every gear, and pushing in the clutch doesn't affect the noise or make it go away. In the vid, I had it all the way to 6th and "highway speed" toward the end of it. I tried to get out and see where the noise was, but I couldn't quite get the timing down to do that. I tried moving the wheels in gear with the car off and I couldn't replicate the noise.
I think it's going to end up on my friend's lift some point this week. This one has me stumped. With another set of ears, it may be easier to pinpoint. Maybe an output shaft bearing? I don't know...
Hmmm, interesting noise.
Remind me: Why don’t you think it’s the wheel bearing?
Is it louder on drivers side?
Yeah I think the lift will help.
In reply to CyberEric :
If it was a wheel bearing, why would it get louder in certain gears, and why would I feel it through the shifter? That's the puzzling part.
I am stumped and it's driving me nuts. 
In reply to Tony Sestito :
Yeah I see your point. On the same token, would the output shaft issue change with different gears? Doesn’t seem like it.
I’m concerned it’s inside the trans.
Could it be the clutch? Maybe a part of the clutch coming apart.
By the way, I question your logic that the car is not worth what it costs to have a shop look at it. Is this thing so beat that it’s worth less than say, 2k? I know that’s not why you’re posting, so sorry to derail but I have a car that I bought for $1600 that I might have to drop 900$ on, and I think it might be worth it to have a car that drives right and is sellable. Just a thought if the lift doesn’t help reveal the issue.
In reply to CyberEric :
If I can't figure it out after putting it on the lift, I may bring it to the local Mazda dealer. They are the only somewhat trustworthy shop around here; they have been great with the wife's CX-5 and I've had them service this car before. The car is in decent shape, but it's starting to show its age in areas. It's basically worthless as a trade-in, especially right now.
Could it be the clutch? It's possible, since it's one of the parts that's always spinning. It is getting toward the end of its life, and if a piece of the friction material got loose and is flapping around in there, that would certainly make this noise. Why it gets louder in certain gears is a mystery, but it's feasible.
When I changed the trans oil yesterday, it was super clean. No metal shavings or anything like that at all. If it was an internal bearing, I'd think there would be more chunks of stuff in that oil.
Another thing: the trans still shifts as smooth as it ever has. Whatever is happening is not making it harder to drive.
This is not a clutch noise. Clutch noise would be engine speed related, this is road speed related. Does this car have a chassis mounted output shaft bearing on the side that would have a long axle? If so that is your failing bearing. I have never been beneath one of these!
wae
UltraDork
8/18/20 11:15 a.m.
I've had CVs make a variety of weird noises and vibrations
I'm guessing something dragging on an axle or a CV joint failing.
Any change in sound if you steer? Seems like it'd be clearest if you had it up like in the video, so you could do meaningful sustained steering inputs at speeds where it's making that noise thoroughly (which would be hard to do while driving).
Any significant change with steering would seem to point harder toward CV issues.
EDIT: I'm not sure that no change with steering would exonerate the CVs, just to be clear.
No changes in sound when steering, which is why I'm skeptical of it being a CV joint. I mean, it still could be, but clicking while turning is a telltale sign of them failing, and they don't do that at all. Then again, if they are really screwed, they would probably do it all the time, right? Then there's the whole thing about it being louder in 4th, 5th and 6th, and while I'm touching the shifter. So, so strange.
On the output shaft theory:
Pic quality sucks, but that's the CV shaft and the "output shaft" (if it even is that). The passenger side CV shaft inserts into that shaft in the 2nd pic. I'll be checking that while it's on the lift.
I also looked into getting a transmission again. I can only find one vendor that sells a remanufactured one, and after it's all said and done, I'm looking at around $4,000. That's absurd and not happening. They don't make a bearing/rebuild kit for this transmission that I can find; I would have to order all the bearings/seals/etc piecemeal. They only made this trans for 3 years, and it only came in the 3 and 6, and the manual take rate in those cars was not high. It's almost cheaper to do a complete Mazdaspeed 3 swap, including engine, suspension, etc, than getting my hands on one of these things if that is indeed what is wrong.
Or, alternatively, I could just LS swap it.
Anything but a transmission internal problem would be a relief at this point!
Definitely sounds like funky CV axle or something rubbing. The one I encountered recently was a wheel weight hitting the caliper on it's way around.
From your photos I see that it does have a support bearing for the output shaft. 90% sure that is your origin. No surprise to me that you feel it and hear it differently with your hand on the gear stick. The noise is a vibration that is induced into the engine structure from that bearing, and the gear stick is the farthest thing out the end of the vibrating structure that has hard connections in two planes. Think twanging like a jews harp.
I am really, really hoping it's the intermediate shaft bearing, because that's the cheapest of all fixes! The bearing and seals are about $50 total from the dealer. After listening to other vehicles with failed carrier/intermediate shaft bearings, the sound is similar.
Whelp....
Put the car on the lift today. After much poking, prodding, and listening, we determined that it's the transmission. Specifically, it's likely the output shaft bearing. Looks to be a "take the whole trans apart to find out" kind of deal. This sucks, but I can't be too mad. This has been the first major issue in nearly 9 years and 185k of driving.
So, now I am hunting for another trans. If I can find one reasonably priced, I'll swap it.
I was going to say intermediate bearing or output shaft bearing. Glad you found it. Sorry about the repair
