Outer brake pad more worn than inner

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I changed the front pads on an 05 accord today and noticed that on both sides (passanger and driver) in front the Outer brake pad more worn than inner pad. I also noticed that the dust boot on the caliper piston is ripped on both calipers as well, this will be replaced later this week, can this be a cuase of this wear or is this slide pin related? Thanks
 
Originally Posted By: Merkava_4
Either the slide pins are stuck, or the pad ears are rusted in their clips.

If its is the pins being stuck, can they be saved or is a new set needed?
 
Originally Posted By: zvm77us
If its is the pins being stuck, can they be saved or is a new set needed?


They can be re-used as long as they're straight and not pitted from rust.
 
For me the rear caliper bolts had no grease at all, so they were not sliding evenly. Which lead to uneven pad wear. Cheap repair.. you probably just need boots, clean pins and the hole, grease....
 
I had the opposite happen to my 1998 CRV. Nothing wrong with the brakes but I routinely examine the disc brake pads (originals, never been replaced) with a strong flashlight, and the outer fronts still had half of the original pad thickness at 70k miles. Of course I can't see the inner pads from the outside. On a whim, I opened up the calipers and the inner pads were down to 1.6 mm thickness (the wear limit, I believe) on both front brakes. The calipers move freely and are not stuck.
 
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Outer pad worn means the slides or pins are causing a bind and in need of cleaning and lubrication. Inner pad wear is a binding caliper piston not returning.
 
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Originally Posted By: Lubener
Outer pad worn means the slides or pins are causing a bind and in need of cleaning and lubrication. Inner pad wear is a binding caliper piston not returning.


Well, I don't think I have a binding caliper piston. My brakes are normal. I get good gas mileage, and the front brakes are never too hot to the touch. When approaching a stoplight, I sometimes shift to neutral to test for brake binding, and the car always freewheels. When stopped on a very slight grade or incline, the car will roll freely if I don't apply the brakes.
 
Originally Posted By: berniedd
Originally Posted By: Lubener
Outer pad worn means the slides or pins are causing a bind and in need of cleaning and lubrication. Inner pad wear is a binding caliper piston not returning.


Well, I don't think I have a binding caliper piston. My brakes are normal. I get good gas mileage, and the front brakes are never too hot to the touch. When approaching a stoplight, I sometimes shift to neutral to test for brake binding, and the car always freewheels. When stopped on a very slight grade or incline, the car will roll freely if I don't apply the brakes.


It could be a very slight binding and the weight of the car can easily overcome it. Over thousands of miles it adds up. I think you still have a binding problem and need a good cleanup and lube job as others mentioned.
 
The brake design on my Scion (rear brakes) is terribly well known for this. As others mentioned, likely a sticking dry slide pin.

I put new hardware kits in mine, switched to Syl Gylde grease from NAPA and have had no issues since.
 
I also forgot to mention that the inner pad (that have lots of meat left) on both sides have these deep grooves on top and bottom of the pad going like an arc, very similar to the link below:
http://www.monroebrakes.com/images/support/english/commonpadnoise1_img_lg.jpg

monroe on their website writes the reason for such grooves is "No working contact with the rotor surface leaves hard oxidation (rust) spots that machine away the surface of the pad. Grooves like this can lead to noise events, and decreased pad-to-rotor surface area contact may increase stopping distance." this makes me think that the inner pad isn't contacting the rotor correctly but the outer is and that is why the outer pad is more used up, what do you think?
 
Originally Posted By: demarpaint


It could be a very slight binding and the weight of the car can easily overcome it. Over thousands of miles it adds up. I think you still have a binding problem and need a good cleanup and lube job as others mentioned.


Nah, I don't think I have a binding problem. The right and left inner pads were equally worn. Very unlikely a binding problem will be on both left and right inner pad locations simultaneously and to the same extent. I had bought a replacement set of pads previously and did a thorough brake job at the time I found the worn inner pads, and I assure you everything else was in proper order.
 
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Originally Posted By: berniedd
Originally Posted By: demarpaint


It could be a very slight binding and the weight of the car can easily overcome it. Over thousands of miles it adds up. I think you still have a binding problem and need a good cleanup and lube job as others mentioned.


Nah, I don't think I have a binding problem. The right and left inner pads were equally worn. Very unlikely a binding problem will be on both left and right inner pad locations simultaneously and to the same extent. I had bought a replacement set of pads previously and did a thorough brake job at the time I found the worn inner pads, and I assure you everything else was in proper order.

If the outer pads are worn more than the inners, there's an issue. They should be close if things are working properly, serviced or not. Vehicle weight would have nothing to do with it provided the wheel bearings are in good shape without slop.
 
Originally Posted By: berniedd
Originally Posted By: demarpaint


It could be a very slight binding and the weight of the car can easily overcome it. Over thousands of miles it adds up. I think you still have a binding problem and need a good cleanup and lube job as others mentioned.


Nah, I don't think I have a binding problem. The right and left inner pads were equally worn. Very unlikely a binding problem will be on both left and right inner pad locations simultaneously and to the same extent. I had bought a replacement set of pads previously and did a thorough brake job at the time I found the worn inner pads, and I assure you everything else was in proper order.


No disrespect intended, but if the job was done wrong odds are it was done wrong on both sides. Case in point, I have seen people slap brake pads on and do no cleaning or lubing, or lubricate parts with too little grease, or the wrong grease. If everything is done correctly the pads should be wearing very close to even.
 
Originally Posted By: zvm77us
I also forgot to mention that the inner pad (that have lots of meat left) on both sides have these deep grooves on top and bottom of the pad going like an arc, very similar to the link below:
http://www.monroebrakes.com/images/support/english/commonpadnoise1_img_lg.jpg

monroe on their website writes the reason for such grooves is "No working contact with the rotor surface leaves hard oxidation (rust) spots that machine away the surface of the pad. Grooves like this can lead to noise events, and decreased pad-to-rotor surface area contact may increase stopping distance." this makes me think that the inner pad isn't contacting the rotor correctly but the outer is and that is why the outer pad is more used up, what do you think?


Yes, that can happen. If that's the case, there will be severe rusting of the rotor, on the area where the pad touches, all the way around in a ring. The place on the rotor where the pad touches needs to be clear over the entire area of the pad. Replace rotors that have the "ring of rust".
 
Originally Posted By: Merkava_4
Either the slide pins are stuck, or the pad ears are rusted in their clips.


+1 It seems like something is sticking. I would replace the hardware an pads personally. You might also consider a Brake Pad Drag Reduction Clip when you do it. It will apply pressure to the pads to separate. I am going to be putting them on my Equinox in the next few weeks but I had a post on BITOG and it seems like it does a nice job at keeping the pads separate without changing the braking characteristics
 
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