Brake Rotor Blunder

[MCTeeJ]

Hey all,

So this weekend I attempted to swap out my front pads and rotors for replacements. I didn't realize until after I had driven the car for a day that the rotors are a few mm smaller than oem (started to notice the pads were marking the very outside edge of the rotor). I'm not sure if this is an issue with centric or my supplier (likely the supplier).

My stock rotors still have plenty of life left. Considering I've only put about 5 miles on the correct pads/wrong rotors, should I be able to throw my old rotors back on with the new pads and just re bed them? or is it likely I'll have an issue with uneven wear on the pads?

pictured is the old rotor (used a rubber mallet but the marks will come right off)
and the new rotor on the car

[HimBRZ]

I'd say you won't have a problem, but I can't speak for the anal retentive among us.

[MCTeeJ]

Originally Posted by HimBRZ

I'd say you won't have a problem, but I can't speak for the anal retentive among us.

I think I'll be alright too. I'm gonna attempt it tonight hoping everything goes smoothly. I'm just not that confident because this was the first time I've done brakes and I'm not well versed like others.

[ls1ac]

Take the small ones off and have the seller replace with the right ones. When you have the pads off look to see if there is a step near the outside edge, if so, remove the step with a sander/file to make it flat.
A small change in the outside diameter makes a difference in stopping power.

[MCTeeJ]

Originally Posted by ls1ac

Take the small ones off and have the seller replace with the right ones. When you have the pads off look to see if there is a step near the outside edge, if so, remove the step with a sander/file to make it flat.
A small change in the outside diameter makes a difference in stopping power.

Oh I believe it. I'm pretty sure I'm just gonna have to eat these rotors though. I messaged the owner of the company this morning and his only reply was "dang." and then left me on read. I bought them months ago and slightly used them so it's fair that the problem is on me at this point. Hindsight is 20/20 I guess.

[humfrz]

Like said, I reckon the old rotors will be just fine with the new pads, no longer than you used the new rotors.


humfrz

[ls1ac]

Looking at the picture on the right, it seem that the pads miss the inside half inch of the rotor; and overhang the outside. About a 20% loss of area.
If you ordered the rotors for the BRZ/FRS then the company was at fault and sent the wrong ones. Get them to correct the mistake on there part. If they will not, let us know who they are.

[gravitylover]

Do you still have the stock rear rotors? I've been looking at new fronts and there are two different sizes, one if you have vented rears and a different if you have non vented. Take a look and see what you have then measure what you got and look at the specs. If the company you ordered from didn't specify you likely got the wrong ones and may be stuck with them depending on your negotiating skills.

[MCTeeJ]

Originally Posted by ls1ac

Looking at the picture on the right, it seem that the pads miss the inside half inch of the rotor; and overhang the outside. About a 20% loss of area.
If you ordered the rotors for the BRZ/FRS then the company was at fault and sent the wrong ones. Get them to correct the mistake on there part. If they will not, let us know who they are.

I messaged the owner again last night and basically said I wasn't happy with the outcome of this whole thing. He sent me a phone number and said to get started with the returns department. I called the number and they then told me to send an email stating everything I said in the phone call....Today will be interesting.

[MCTeeJ]

Got the old rotors back on and put everything back together. You can really see the difference with everything side by side. Bedded the pads and the car stops.

I do have a question, though. When free spinning the wheel on both sides before I bedded the pads it sounded like I could just barely hear the pad contacting the rotor. Is that somewhat normal for new pads? When I had the incorrect rotors on the wheel wouldn't free spin at all, but only on one side.

[ls1ac]

When inserting the pads the pistons may or may not push the pads against the disk.
This is normal. Very normal to drag.

[highway7]

The pads should just slightly ride ontop of the rotors, so a scraping noise is normal. Otherwise, if there is a gap between the pad and rotors dirt will get inbetween.



On RockAuto, you are able to order 277mm or 292mm rotors. You must have the 277mm rotors, which is only used on 86/brz in certain markets as a stripped down "purist spec" version. This "purist spec" is not sold in North America.

[MCTeeJ]

Originally Posted by highway7

The pads should just slightly ride ontop of the rotors, so a scraping noise is normal. Otherwise, if there is a gap between the pad and rotors dirt will get inbetween.



On RockAuto, you are able to order 277mm or 292mm rotors. You must have the 277mm rotors, which is only used on 86/brz in certain markets as a stripped down "purist spec" version. This "purist spec" is not sold in North America.

That makes enough sense to me. However, wouldn't this require a new caliper and pad setup? I feel like that's more work for Toyobaru, but knowing them they probably recycled parts from a corolla or outback or something.

[Tcoat]

Originally Posted by MCTeeJ

That makes enough sense to me. However, wouldn't this require a new caliper and pad setup? I feel like that's more work for Toyobaru, but knowing them they probably recycled parts from a corolla or outback or something.

You would be floored by the number of rotors that are the same even across totally different brands. The only difference is the part number. They all can have different caliper and pads but still use the same rotor.