mz3bo

Hi,

As you can see in my previous post, I have an issue with vibration in the steering wheel under highway speed braking situation. So this is my second set of new OEM rotor/pads within roughly 3000mls and I am starting to have some light vibration again.

So today, right after a 20mls driving at 4F outdoor temperature, I measured the rotor temp with an infrared thermometer. To my surprise, I notice that the first 1/3rd of the rotor (from the center) was at 92F, the second third at 130F and the last third (outer of the rotor) was at 192F ! That was identical on both side. This is for the front rotors (L/R)

Now, is this something normal ? I have new rotor and pads (drove about 1200 mls so far).

Thanks and happy holidays
Bo

N_Jay

The outside has les material to help cool it and is traveling a lot faster across the pads.

mz3bo

Hi,

I tend to understand this differently. The greater the distance, the longer it will cool and the lesser it will touch the pad surface. This said, the outer part of the disc at 1oclock will touch the pads suface lesser in 1 complete rotation VS the inner part of the disc (closest to the hub).

What do you think ?

Thanks

N_Jay

I think we can do a few experiments to see which effect is greater.
I doubt the pad cools the surface significantly.

STLML350

My first thought is to bleed your system if your warping rotors this fast, front and rear. The OD of the rotors should run hotter, more surface area crossing the the pad faster then the smaller diameter and then you have more mass in the center to ack as a heat sink. Also check to see if brake pistons are fuctioning proper.

mz3bo

Please take a look at the picture, what do you think...

STLML350

They look good to me, you are not scoreing the rotor ID or the OD, looking at the temps again, they dont look to high, I know I cant touch my rotors after I pull in my driveway and stop. I go back to have you had your brake system bled. Are your shoes hanging up, are they wearing more, inside to outside per side?

mz3bo

Hi,

Did you notice the blueish color of the OD and some part of the ID ?

Thanks

STLML350

Let me first say, I am not an expert, I can only relay my thoughts and or the things that I would look into.
1 Did you start with all new parts.
2 If yes, then were the caliper s in good working condition? Do they retract, are the seals good?
3 You still have not noted if system has been bled or or if pads are wearing evenly.
4 Dumb question, are you a two footed driver, are you riding the brakes with your left foot, you would be suprised how many people do this.
5 Looking at your rotors, at the amount of miles noted, your already getting lips top and bottom. I have a few thousand miles already on my new rotors and ceramic pads and I nave not worn through the cross hatch grind on my rotors yet.
6 Yes, they are starting to blue, are you purchasing good parts from a quality distributor?
Unless I have a major issue I do not use dealers, find a good shop near you that works on Euro cars, make friends with them, someone you can trust to give accurate info.

Ausmbtech

What brand pads and rotors are you using?

Is it just yourself driving the car or other drivers as well?

Are you mainly doing city driving or highway driving?

How long have you had the vehicle for?