I have a 2004 MCS and have few issues that maybe you all can tell me if they are going to be problems.

1. I can see some rust on one of my rotors. It is on the ring inside of the flat surface the brack pads actually touch. I am not sure of the technical term. The rust is on the horizontal plane of the ring (top side). Is this normal or should it be replaced?

2. I check my computer quite often and I noticed Monday that my "Average Speed" went from 45.6 or something to 0.3. What happened to my average speed and is this something to worry about? It has gone up to 0.6 over the last few days and all of the other setting are the same.

Thanks!

 

Have you gone ahead and reset the average lately? Scroll to the average speed and then hold down the button for a few seconds to reset it.

 

If I did it was on accident. That might explain it. I did not even know that you could reset it. If that was the case would my current average be 0.3 after 3 days of driving? I am not sure how it calculates the number. Thanks!

Jason

 

The rotors are made of Cast Iron, they will rust.

They come from the factory with a coating that burns off and then the iron is exposed to the air.

You can paint this area with a high temp paint and it will stop rusting.

I have seen this done, I have not done it myself.

 

No, it shouldn't read so low. But mine shows my avg speed to be around 30mph and I know I am always going faster.

 

I called my service department and they told me that the "Average" was not intended to be a life time average but a trip average. They said eventually it would have too much data and basically get funked up. So I reset both of them and everything is back to normaly. They confirmed that the rotors will rust and that it is normal.

Thanks for everyone's help!

Jason

 

I too noticed that my average speed calculation seemed to "reset" all by itself. Mine seems to reset when it hits an average of 30 mph, but remains accurate for thousands of miles until I once again accumulate enough data for an average of around 30 mph. It doesn't seem consistent with "data overflow" as suggested by the dealer...there appears to be a trigger point where it resets automatically. I've learned to distrust dealer derived information about the car...they have given erroneous or incorrect information just about every time.

 

100% normal. The part you are talking about is normally referred to as the 'hat'. (if you look at a rotor sitting flat on the plate, you'll see why) High-temp caliper paint, possibly paint designed for use on the grill; will help prevent rust from occurring there, just be careful not to get any on the rotor plates (where the pads contact), or on the wheel-mounting face.