Can I Put Smaller Rotors on My Car

Lindell Frompal · Monday, November 29, 2021

04-27-202005:03 AM #1

Active Member Two Rings

Fitting smaller sized brake rotors?

So i have a bit of a problem. I ordered new brake rotors + pads to replace on my a4 and did the fronts no problem. When i got to the rear and open the box i notice that the new rear rotors i had ordered were much smaller in diameter than the old OEM ones. Size difference is about 400mm in diameter. So when fitted on the hub that would mean i have about 20mm difference when it comes in contact with the brake pads. I wanted to return them but the seller (from germany) said i would have to pay the return shipping wich is about the same as the price of the rotors. So i might as well pay the full price and keep them regardless.

Now im wondering if i can still put these on or if that 20mm difference is too much? I haven't actually tried fitting them since i wanted to return them and not scratch them in any way. Anyone else tried this or do i simply have to cut my losses and order new correct sized rotors?
04-27-202006:29 AM #2

Active Member Four Rings

You bought the wrong size. Why are we having a conversation about fitting the wrong size rotors? Buy the right size and sell the wrong size at a small loss or ship them back at a small loss. Either way you messed up and making them work is just a second bad move following your first bad move.

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04-27-202007:53 AM #3

Veteran Member Four Rings

Originally Posted by EvolutionArmory

You bought the wrong size. Why are we having a conversation about fitting the wrong size rotors? Buy the right size and sell the wrong size at a small loss or ship them back at a small loss. Either way you messed up and making them work is just a second bad move following your first bad move.

This. Seriously.

"I don't understand Audi enthusiasts. They buy a car that looks like a bar of soap, then they spend money modifying it so it looks slightly less like a bar of soap."
04-27-202008:03 AM #4

Veteran Member Four Rings

Originally Posted by EvolutionArmory

You bought the wrong size. Why are we having a conversation about fitting the wrong size rotors? Buy the right size and sell the wrong size at a small loss or ship them back at a small loss. Either way you messed up and making them work is just a second bad move following your first bad move.

x3

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04-27-202009:57 AM #5

Senior Member Four Rings

Originally Posted by Ncie Gyu

So i have a bit of a problem. I ordered new brake rotors + pads to replace on my a4 and did the fronts no problem. When i got to the rear and open the box i notice that the new rear rotors i had ordered were much smaller in diameter than the old OEM ones. Size difference is about 400mm in diameter. So when fitted on the hub that would mean i have about 20mm difference when it comes in contact with the brake pads. I wanted to return them but the seller (from germany) said i would have to pay the return shipping wich is about the same as the price of the rotors. So i might as well pay the full price and keep them regardless.

Now im wondering if i can still put these on or if that 20mm difference is too much? I haven't actually tried fitting them since i wanted to return them and not scratch them in any way. Anyone else tried this or do i simply have to cut my losses and order new correct sized rotors?

your diameter is way too off. Return them.
04-27-202004:49 PM #6

Senior Member Four Rings

Don't use, and why order from germany?? Assuming ya don't live in Germany, lol. Sounds like ya ordered b6 or cabrio/diesel rotors.

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04-28-202012:19 PM #7

Veteran Member Four Rings

Originally Posted by Jayz691

Don't use, and why order from germany?? Assuming ya don't live in Germany, lol. Sounds like ya ordered b6 or cabrio/diesel rotors.

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He lives in Sweden.
04-28-202012:57 PM #8

Veteran Member Four Rings

And given he's in Europe, they have different sized optional brakes on the b7 whereas all B7 A4s here in the US got the same brakes. So while its not as simple as "just buy the 288mm ones, bozo" the responsibility is on the buyer/OP for getting the wrong shit.

I don' know what particular size brakes you have OP, but to echo everyone else, you fucked up and bought the wrong ones. You can't use them. get the correct ones and either return the ones you have to try to sell them on Craigslist or whatever similar thing you might have in Sweden.

-CP
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Former U S P CLUB MEMBER #136
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04-28-202002:16 PM #9

Senior Member Four Rings

Figured he was over there somewhere. Thats why I mentioned different sizes, like diesel and Cabrio has smaller brakes, I believe.

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05-03-202004:34 AM #10

Active Member Two Rings

Yes i have been told by a few people that it should totally be possible to have different rotor sizes. That's why i posted here because i couldn't see how that would work after looking at the caliper and pads in the front. They refuse to pay the shipping for me to return it so i had to just pay for them and toss them in a corner in my garage:/ not really any sort of brakerotors that i can sell on the Swedish craigslist unfortunately..

I buy from Germany like everybody else in Europe becuase that's where all the parts come from anyway and it's cheaper cutting out the middlemen. Not sure how i managed to order the wrong ones really can't explain it must have been in a rush or something because they are rear rotors that i bought while looking for front
05-03-202011:21 AM #11

Veteran Member Four Rings

Yea I mean you could run a smaller rotor, but it�s going to mean you need new calipers or new caliper carriers. It�s cheaper to just order new rotors than to try to make the smaller ones work. And frankly even if it was cheaper to downgrade the brakes, why would you want to downgrade the brakes?!

-CP
2008 Brilliant Black Unicorn (2.0t S-Line Ti 6MT Avant) - R8 V10 Coils and Spark Plugs - AMI retrofit - Mk2 RNS-E
2012 Q5 2.0t - Stock Mommy Missile with new timing chains
Former U S P CLUB MEMBER #136
2004 A4 1.8TQ 6MT USP - APR Stage 1+ - FSI Coils - BKR7EIX-11 - B6S4 Front + B7A4 Rear Brakes - 034 Street Trans Mount
SOLD -- 2006 A4 2.0TQ Avant Tiptronic