do brake rotors need to be the same size?

[OnTheEllipse]

really hoping this isn't as stupid a question as it feels:

I have a 2001 SR5 that I'm replacing the rotors and pads on. I ordered a pair of Brembo 43512 04020 rotors as replacements. I have the old rotors off and laid them on top of each other just to compare, but the new rotors are a little smaller in diameter. Is that normal/ok or did I buy the wrong part?

The center section is the same, just the diameter is a bit smaller.

these are the rotors in question:

2001 Toyota 4Runner Front Brake Disc 43512 04020

Any help would be appreciated. I'm on jack stands right now

 

[lbhsbz]

How much smaller? A millimeter isn't gonna hurt anything. As long as the pads don't overhang the rotor, it's good. There are 2 brake systems on 3rd gens....the difference in rotor size is almost an inch. These are not interchangeable.

 

[NOT ME OR SOMEBODY]

How much smaller? A millimeter isn't gonna hurt anything. As long as the pads don't overhang the rotor, it's good. There are 2 brake systems on 3rd gens....the difference in rotor size is almost an inch. These are not interchangeable.

X2.... brakes are something you don't want to be sure about.

 

[tbst]

X2.... brakes are something you want to be sure about.

Fixed.

 

[NOT ME OR SOMEBODY]

yeah thats what I meant. thanks

 

[JohnsD90]

You probably got the ones for a 15" wheel, i accidentally did that too, return them and order the proper size ones. It's no good to have the overhang, you lose braking power.

 

[A.Wilson013]

In a word....

Yes.

 

[z28forlife]

I'd definitely get the right size, brakes are what keep you from dieing everytime you speed up...lol

 

[OnTheEllipse]

You probably got the ones for a 15" wheel, i accidentally did that too, return them and order the proper size ones.

That's what happened. Thanks for the replies. I had to pick a pair of OEM's up from the dealer in a pinch (at twice the price of the Brembos).

I'm going to put these here in case it helps the next googler not make the same mistake:

2001 Toyota 4Runner rotor sizes

15" Wheels: 43512 04020
16" Wheels: 43512 35210 (the more common size, I believe)