Year, Make and Model:
2002 Honda Accord EX, 4dr, 4cyl
When I brake, the car pulsates when the car gets to 20MPH from 50MPH. I know that this is usually a sign of warped rotors.
Car shop verdict:
I had my car checked at a couple local repair shops. Most of them told me to replace the front rotors. One repair shop told me that I should repair both the rotors and the brake pads because they go hand-in-hand.
Questions for Cartalk members:
(1) What rotors (brand) should I get installed on the car? I know of Brembo, but what else?
(2) Should I get both rotors and brake pads replaced?
Year, Make and Model:
- You do not have to use Brembo. Any brand named rotor from a local parts supply house will be fine.
- Servicing the rotors (either by machining or replacing) is the proper way of performing a brake job so yes, the rotors get taken care of. Not doing this can open up a can of worms and any shop who doesn’t do this is lax.
You should keep in mind that not all brake shudder and pulsation is due to warped brake rotors. This can also be caused by a loose wheel bearing or suspension component such as a tie rod, ball joint, etc.
The rotors can be checked to make sure they’re warped before blaming this problem on the brakes. Odds are that it is the rotors; just pointing out that it’s not always the case.
Hi, Thanks, I appreciate the help!
ok4450 is right on all that he said, but I would add a few comments.
One, if rotors are warped, they can be surfaced, but often they will warp again soon.
If rotors are not warped, or grooved, they do not need to be “turned” on a lathe except to clear the glaze, which can be done with emery cloth. Rotors do need to be measured with a caliper or a micrometer for thickness, if they are worn too thin they should be replaced. the same for pads, replace only if worn. warped rotors do not always mean worn pads. Since the wheel bearing race is part of the rotor, the rotor needs to be checked for a loose or incorrectly adjusted retainer nut.
Hi ok4450, I was told by my local mechanics that my rotors should be replaced and NOT machined.
Is it true that if the rotors need to be changed, the brake pads also need to be changed?
There is nothing wrong with machining rotors. It’s often stated that machined rotors will warp more easily but this is not exactly true. They will warp more easily IF the rotors are machined down to the minimum thickness or below that.
I’ve machined more rotors than I can remember and have never had a problem with it.
Most rotors have about .030-040 that can be removed before they reach minimum thickness.
(Some rotors like the ones on my Lincoln have about .050-.060. They’re meaty so to speak)
A decent mechanic should be able to tell by making a light cut on the rotors whether they’re going to clean up quickly or not. (Machining rotors requires multiple passes; they are not done by making one cut, although some foolish mechanics may try it.)
The main reason behind replacement is a matter of economics. It’s weighing the cost of machining against the cost of a new rotor.
Yes, pads should be changed if the rotors are replaced or machined. Something else to keep in mind (and often seldom done) is that machined rotors or new rotors should be carefully cleaned before installing them. This removes microscopic debris from machined rotors and any rust preventative coating from new rotors. Sometimes that coating is visible; sometimes it’s not.