Grinding noise at hard stop.....

[noupf]

I have a 2015 Ram Sport 4x4 with 90k miles. About 3 months ago, i noticed a front end grinding noise when coming down a slight hill will some moderate to heavy braking as I approached a stop sign. It sounded like a worn pad grinding on a rotor ( something most of us know and have heard before ) and the noise only appeared just before the truck came to a complete stop. After a quick inspection, I confirmed that the pads and rotors were not overly worn and there were no signs of anything grinding or digging into the rotor. All looked good for rotors with 90k on them and pads with 55k on them.

Over the last couple months, the noise has been there occasionally, but again, it only happens with moderate to heavy braking and it only pops up at those last few mph's just before the full stop. If i'm doing 75mph and exiting a highway, i can hit the brakes hard and ride it hard to a full stop, but the noise will only appear in the last second or two before I completely stop. If I do the same thing, but this time, ride the brakes a bit more softly to the same stop, there will be no grinding.

Original pads were changed out around 35K miles to Carquest Professional Platinum Ceramic Brake Pads ( mainly bc i wanted less brake dust on my wheels ) and the pads have been great for the 50k miles or so that i've had them. I'd say the pads have a 1/3 or more of life left in them, so they are nowhere near shot. The rotors with 90k on them look fine as well. There are no shakes , noises or vibrations while driving or braking, well, not till the grinding starts anyway lol.

Some people have mentioned wheel bearings / hubs an others have said pads and rotors. I'm at a loss here.


Thoughts??

 

[Jeepwalker]

Noises are difficult to diagnose over the internet. That being said:

Jack up each wheel and with your hands on the tire, in a 6:00-12:00 positions, shake back n fourth vigorously (with force). If there's ANY movement at all, your wheel bearing is failing. But wheel bearings can be in a long state of failure for months and progressively get worse. Then sometimes they can just fail catastrphically. But usually they fail gradually.

Could also be another driveline issue (Front drive axles, driveshaft, u-joint, ball joint, differential/s, etc), or maybe something else brake related (cracked rotor?). You can chack rear bearings by lifting up/down (vertically) on the wheel. On the rears you should expect a minor amount of free-play. Fronts should be no movement however.

Sometimes it helps to have a helper drive to mimic the conditions while you hang your head out of the window, or stand on the street near where the stopping would occur. I had to run alongside one of my vehicles while my wife drove ...and only then could I really hear the noise I was hearing was coming from the Pass wheel. Then on a jackstand, I had her put it into gear and put a long wood stick on the inner wheel bearing and the other end to my ear and at that point I could REALLY hear the bearings grind around inside the hub assembly.

Good luck.

 

[noupf]

Yea I realize it’s hard to diagnose on the web. Thanks for the tips.

I should clarify, it’s definitely a rotational heavy sort of grinding noise.

 

[chopperman1]

I'd be looking at the rust/ridge line on the rotors

 

[KoboldTaco]

I'd be looking at the rust/ridge line on the rotors

Yup!

1 - tires off
2 - Do the suspension check for worn bushings etc - but, I’m suspecting brakes, or as said here ridgeline wear. That can indicate you are wearing on the edge of the rotor, which in most cases is because your pad is gone, rotors shot and your grinding on the pad casing. You should pull the caliper off and look closely at the wear. Wheel bearings can also be checked with a scope to listen and see if they are crunchy.

I’ve also experienced this with cheap pads, dust between the rotor and pad; then under load - grind that sounds like metal on metal - which with semi-metallic is actually true. I fixed it by adding a dust cut as the pads I had at the time were one solid unit Without any cuts to allow dust to escape more easily. Good luck!