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Yep, you're describing exactly what happens. Not all of us get the squeak/screech sounds. I've gotten dozens of people's pads replaced, which has resolved the issues for them. There've been others, myself included, where, instead, the rotors were ground or replaced, and the problem returned as soon as they were pulse glazed by the early revision/original pads.
Also, this is --- and the rep is ---- in case you were interested. (Delete this part if not appropriate.)
 

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Not his fault - it's the way the TSB is worded. I have the luxury of following thousands of Ascents across three different forums/groups, so, I see the results of interpreting it the way he is.

This is a pulse glazed rotor. Mine looked just like it (twice). LOOKS warped. Isn't. Mine are still on my car, at almost 70,000 miles, but with new pads (2nd revision), and are running fine. The third pad revision is even better (but I missed it by two weeks).

6080
 

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I printed the photo you attached and will take it with me. I'd like to add; I looked at my rotors through the wheel with fair light and felt them as well. They did not have the banding yours shows. Perhaps it was the light and angle you captured in the photo. Was there any felt change when running a finger over the rotor and the glaze?

Is there a part # for the 3rd revision pads? If they do decide to replace them, or they did, I'd like to be able to determine what rev I have or can request.
 

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I printed the photo you attached and will take it with me. I'd like to add; I looked at my rotors through the wheel with fair light and felt them as well. They did not have the banding yours shows. Perhaps it was the light and angle you captured in the photo. Was there any felt change when running a finger over the rotor and the glaze?

Is there a part # for the 3rd revision pads? If they do decide to replace them, or they did, I'd like to be able to determine what rev I have or can request.
You'd need a micrometer to pick up those differences...our sense of touch wont do it. Good luck and keep us informed!
 

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Yep, and you'd need to de-glaze it first, otherwise, the glazing stripes will measure as warping. Regardless, get the new rotors. That gives you an extra 15,000 miles on your rotors. ;)
 

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Can I ask for my replaced parts back? Not sure how that works under warranty.
No. Subaru is paying for them (technically, for the replacement), and will want them back or disposed of in a select manner.
(I mean, you can ask, but the answer should be no)
 

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The TSB description and part # is PAD KIT-FRONT DISK BRAKE** 26296XC00C
Is that the 3rd rev part number?

The TSB is dated 8/18/20
 

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Not his fault - it's the way the TSB is worded. I have the luxury of following thousands of Ascents across three different forums/groups, so, I see the results of interpreting it the way he is.

This is a pulse glazed rotor. Mine looked just like it (twice). LOOKS warped. Isn't. Mine are still on my car, at almost 70,000 miles, but with new pads (2nd revision), and are running fine. The third pad revision is even better (but I missed it by two weeks).

View attachment 6080
And this photo make me think its a combination pad/rotor problem. You are basically seeing the vanes from the inside of the rotor which will be hotter than the air void between them. There will be temperature differences across the face of the rotor (minute differences relatively) but it shouldn't cause pad deposits and pulsing. Interesting because I've only seen this type of pattern on a severely worn rotor, or a rotor that wasn't getting enough airflow for cooling. I haven't spent much time under my car, but I do have an oil change that is due...I'll definitely be looking at what Subaru did to channel air to the brakes as most cars have fins/vanes or other methods of directing air towards the back of the wheel. Curiosity officially raised!
 

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Is there a part # for the 3rd revision pads? If they do decide to replace them, or they did, I'd like to be able to determine what rev I have or can request.
I think you're stuck with them following the wording/letter of the TSB exactly. Is it possible that your rotors warped for some reason? Sure. Is it likely? Probably not - but there have been three confirmed sets (and all the rest has been pad bedding issues).

Regardless, the pad part number is:
26296XC00C

It replaces the previous revision and the original.
6081


Note that there's no rotor change - just three versions of the pads.

Here's the singular rotor set (no revision):

6082
 

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And this photo make me think its a combination pad/rotor problem. You are basically seeing the vanes from the inside of the rotor which will be hotter than the air void between them. There will be temperature differences across the face of the rotor (minute differences relatively) but it shouldn't cause pad deposits and pulsing. Interesting because I've only seen this type of pattern on a severely worn rotor, or a rotor that wasn't getting enough airflow for cooling. I haven't spent much time under my car, but I do have an oil change that is due...I'll definitely be looking at what Subaru did to channel air to the brakes as most cars have fins/vanes or other methods of directing air towards the back of the wheel. Curiosity officially raised!
There's air vents on the rotor shield (more like air scoops) that ram air at the rotors.
 

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As an FYI, I really didn't notice the shudder until the weather cooled significantly actually. Summer temps over 100 and now highs in the 60's. Probably doesn't matter, but just thought I'd point this out. I did several mountain roads with the air temps warm to hot without noticing. Just recently the issue came back as it did last winter driving in cooler weather; wet and snow.
 

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Got the car back today. They installed 2 new front rotors and 1 new brake pad kit 3rd generation. Works like they did new. I have a nice service department. Chatted with the service writer about the situation for a while. No charge to me of course.
 

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So glad to hear they replaced the front pads. I suspect you'll be fine now. I have Generation 2 (on original rotors), and they're still doing well at 16,000 miles.
 

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As an FYI, I really didn't notice the shudder until the weather cooled significantly actually. Summer temps over 100 and now highs in the 60's. Probably doesn't matter, but just thought I'd point this out. I did several mountain roads with the air temps warm to hot without noticing. Just recently the issue came back as it did last winter driving in cooler weather; wet and snow.
I asked the service writer about this experience; the problem more apparent when cold and wet. He said that the water cools off the open areas of the rotors quicker than the vane areas which have more mass, causing them to warp. So, to summarize, the rotors get hot, get splashed with water, slush, chill quickly but unevenly due to the vanes connecting the two rotor plates and they warp. He said sometimes they turn them, some times they replace them. The work order I got returned to me with my receipt says the runout was more than .5mm. I'm attaching a photo of the work order including the parts replaced;
6124
 
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