When I picked up my new brake rotors for my Jeep the guy at the parts counter advised me to carefully clean the brake rotors of oils including oil from my fingers to prevent warping. This was new to me and got me thinking about warped brake rotors and reminded me that I have not had to deal with a warped rotor in a long time.

The first thing I learned years ago was that the pulsing sensation we called a warped brake rotor is not actually warping. You can put a dial indicator on the face of the rotor and spin it around and it will read very little run out when it is making a pounding sound when the brakes are applied. You can measure it all the way around and you will find very little difference in thickness either.

The real cause of the shudder is a chemical change in the metal of the surface of the rotor. You can sometimes see it but most of the time you can’t. Turning the rotor cuts off that surface layer making the rotor run smooth again adding to the warping myth.

The rotor surface chemically interacts with the brake pads under the heat of braking. Most of this interaction occurs during the bedding in process of the brake pads. Many high performance and racing pads have a critical bedding in process to establish the correct chemical bonding between the two materials. Usually this involves making controlled braking maneuvers at predetermined speeds to generate the heat needed for the reaction to take place. It is important not to come to a complete stop during the process so that the interface layer is kept consistent around the rotor face.

This leads to why rotors “warp” and how to avoid it. The interface layer is constantly maintained as the rotor face and the brake pad material wears away. A new layer is constantly formed with each use of the brakes.

If you come to a complete stop with the brakes hot, the reaction will continue under the pads where the heat cannot dissipate. If it is held there too long, it will create a bond that is a bit stronger or weaker than the area next to it on the rotor. As the rotor develops these uneven spots where the coefficient of friction is grater that the surrounding rotor face, the brakes will give the characteristic chatter that we call a warped rotor. The pulsing in the pedal will feel like the rotor is pushing the pads away from the surface.

I tried a lot of things before I finally got away from “warped” rotors. I tried the expensive rotors. I tried the cross drilled and slotted rotors. I tried various pad materials.

The thing that I found that helps more than anything is a simple driving technique. Some people call it the Limousine stop. I call it a creeping stop. If I suspect that my brakes are hot when coming to a stop, I will aim to stop a bit short and then just before the Jeep stops and is ready to rock back, I let off the brakes and let it creep forward about a half turn of the wheel. If I have to stay stopped like at traffic light, I will creep forward again another quarter turn of the wheel to help even out the heat buildup in the rotor.

There are times where it may not be possible to make such a stop. For example in an emergency or if you have to spot unexpectedly. You may also have to hold the brake longer than you wish thereby creating a hot spot. If this occurs, I repeat the performance pad bed in process and create a new interface layer. Depending on how bad the hot spot is, it may take several repetitions of heat cycling the pads to get them smooth again.

Since I have made this style of stop a habit, I have not had any more trouble with warped brake rotors. I can’t remember the last time I replaced rotor on one of my Jeeps due to chatter.

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As we count down the days to the end of the Mayan calendar, I am thinking back to the last potential apocalypse. I still remember all the hoopla that surrounded the change from 1999 to 2000. It seems many people were convinced that all the computers in the world were going to crash and we would be returned to the dark ages because the computers would not know what year it was.

At first I thought the whole idea was just silly. I had no idea anyone had taken the issue seriously. This is until I got a directive from my company that I had to certify each and every item in the plant to be Y2K compliant. Even in my relatively small plant employing just under 200 people, there were a lot of individual items that had to be certified.

Considering the relative importance of the situation, I first assigned the task to my co-op engineer. As he began to collect the data, and report back his findings to me, I began to realize that there were in fact many people who took the issue very seriously. Some companies were paying big bucks to have their equipment certified.

In order to not take resources away from solving real problems, he and I developed a checklist to quickly verify that the equipment would not self destruct at the stroke of midnight on December 31, 1999.

Naturally our first step was to see if the device even had a clock and even knew or cared what day it was in the first place. We also developed a form letter to send to manufacturers to get a document that added credibility to our own assessment.

Once we realized that not only did our own upper management actually task the situation seriously, but other companies were also taking the issue seriously we began looking into selling our services outside the company. Unfortunately by the time we realized people would actually pay us to do the work, most of the big contracts had already be let to people faster on the uptake than us.

So we just resumed our own process of certifying all the equipment we had and depended on. Naturally most of the stuff we looked at did not have a clock and could quickly be eliminated from the high priority list.

For most things with a clock, it was a simple matter to set the clock to a date past 1/1/2000 and see what happened. Only after we had tested most things on our list did we get stern warning from corporate not to test in this manner unless specifically told to by the manufacturer. Luckily we had completed most of our testing by the time they told us to quit.

One system of particular interest was the phone system. It did have a very important function of keeping the date and time of each voice message. About a week after we had run our clock forward and back again with no ill effects noted we received a dire warning from the manufacturer not to perform such a test. The assured us that it would indeed self destruct.

Sensing this was a scheme to cause us to hire one of their technicians to test for us, I called our sales rep and told her we had already done the test and nothing bad had happened. She informed me we were very fortunate that it had not crashed but was sad that we did not need their tech to test it for us.

Once we had complied huge notebooks of documentation for the equipment in the plant, we began thinking of how to best present the data to management and the auditors. Yes, they actually had auditors to make sure we actually did the certifications and did them correctly.

We first ranked items by criticality. The highest priority items were placed in the first notebook. These were items that would have the most impact on the operation should they fail on 12/31/1999. Of course these were items that might shut down production or make the facility uninhabitable for some reason.

My co-op engineer examined the data and decided in order to quickly point out how thorough we had been we would sort the data in inverse alphabetical order. After all our most important piece of equipment was made by Zerand and there was no point making them flip through the huge notebook looking for the Z’s.

The most rewarding consequence of the inverse alpha sort pattern was that it put the Zurn company at the top of the list. Zurn made the automatic flushers for our toilets and of course we ranked these as critical since no one wants to inhabit a building if the flushers are not working. The added benefit was the not so subtle hint as to where we thought all the data we had worked months to gather really belonged.

The managers go the last laugh on us however as they required us to be on site at the stroke of midnight on 12/31/1999 just to make sure we had not missed anything. We got to ring in the new millennium with a group of engineers and maintenance workers rather than our families. But, they did give us written authorization to have an actual Champaign toast at midnight.

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When my mirror fell off while racing the Rallye de Parris, I causally said to my co driver, “Whats a behind me is not important.” The video shows me tossing the mirror to the back and it hitting the camera lens. The remainder of the video is much better without the big mirror in the way however.

The mirror was tossed into the tool box and forgotten. Now that the Jeep is used for Off Roading, it is nice to see what is going on behind me. I have mounted a nice big mirror on the fender for when the doors are off. But not having the center mirror makes it hard to see the rig behind me at times.

I found the mirror, but the metal dot that glues to the windshield was missing. I found one at Advance Auto that had glue already on it. I had to rim it a but to fit the Jeep mirror. I just used my grinder to trim it down to fit.

To locate the proper place for the bracket, I measured the location on my street Jeep. I made a small x on the outside of the glass with a marker. I then used brake cleaner to clean the inside of the glass.

I pulled the backing off the adhesive and pressed the dot in place over the mark in the glass. i held it a second or two to make sure it bonded. I then cleaned the mark from the outside of the glass.

I let the glue set for a few minutes before slipping the mirror over metal dot. I tightened the set screw and adjusted the mirror so I could see out the back.

I suspect it will take me a while to get used to it being there again. But it will be really nice one the drive to the trail head and when keeping up with the rig behind me on the trails.

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