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Grinding sound from transmission / diff

Messages
91
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18
Location
boonieville
#1
I'm not sure if this is an actual issue, or just a specific condition that doesn't play nice with the ABS system.

So here it is:

If I brake hard enough on a surface with different amounts of traction on the driver / passenger sides, the wheel on the slick surface locks, while the other is still spinning.

This creates a grinding noise, like a large stone being dragged over top of another large stone.


I know abs pulsates when braking hard, so I suspect that the locked wheel is starting and stopping suddenly, violently twisting the two cv joints into / against each other inside the diff.

I figured the diff would allow the wheels to have different rotations with no issue, and that the ABS pulsates the left and right wheels at the same time (I think).

This has happened 2 -3 times on surfaces when the traction is about equal too, but not nearly as noticeable.

Is this normal, or am I going to need to open up my transmission?

If my question isn't clear enough, just ask for more info.

Thanks!
 


OP
mk_not_a_robot
Messages
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Location
boonieville
Thread Starter #4
Could be actually. I'm at home atm, so that means I'm going to test that idea right now.
I'll post what I find.

I think you guys are probably right, it's just that I didn't find useful information on-line for this.
Better safe than sorry.
 


OP
mk_not_a_robot
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Location
boonieville
Thread Starter #5
So I turned of the ECS, holding down the button until the bar on the screen filled.

Stepped on the brakes, still got that grinding.
Looking on-line, apparently it can't be fully turned off. Unless I unplug whatever fuses are connected to that system.


Ill just go with the idea that it is the ABS system, but it does seem to be coming from the driver side wheel area, the tranny is on the driver side around there too.
I dunno. Ill just have to take the wheel off and inspect the parts in the wheel well.
 


Messages
223
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53
Location
Charlottesville
#6
Nothing to inspect, if you want to be sure pull the fuse for the abs system. Some times ABS makes a crunchy crunch noise.
 


Intuit

3000 Post Club
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Location
South West Ohio
#7
The button on the console only affects traction control for conditions experienced without the brake pedal applied; acceleration, cornering. You're right that ABS remains fully engaged.

It's automatic; as my foot goes to brake, my other foot is already stabbing the clutch pedal.

If you believe that the noise is sourced through the drivetrain, see whether the noise changes depending on whether or not it's engaged.
 


Messages
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16
Location
Thornton
#8
Fully active ABS is very noisy, and the pulsations will be felt in the pedal and heard from the passenger wheelwell area as the HCU is right next to the passenger strut mount.
 


OP
mk_not_a_robot
Messages
91
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Location
boonieville
Thread Starter #9
By engaged you mean in gear? If so, it doesn't matter. it does it in neutral as well.

The sound is coming from the drivers side, not the passenger side. So either on the wheel area directly, or where the differential is.

I didn't experience this with my previous car, which is why I brought it up.

I might have to find the fuse that deals with the ABS, and try again.
I just find it odd that a perfectly healthy ABS system would make such a horrible grinding sound.

On the other hand, I'm not really a car guy, I'm getting into it with my ST, but Im new to actually knowing detailed stuff about cars.
So it could easily be completely normal. I don't know.

Ill see if unplugging that fuse (which ever one that is) has un intended side effects, like a CEL if I unplug it, then Ill try it again.
 


Intuit

3000 Post Club
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#10
Deactivating a safety or emissions system will undoubtedly trigger some dash light(s).

https://www.fiestastforum.com/threads/19323-Torque-for-a-steering-related-bolt-needed

Don't know the age or mileage, but you can inspect for loose front-end components.

Never had to engage ABS. Prior car didn't have ABS... or any other nanny for that matter. (nice!)

Last week for the first time ever I purposefully engaged it on an empty icy backstreet but was in a rental Nissan then. Yeah, pulsing, noisy, but no metallic sounds of note.
 




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