[DK on the road]

I Find this a timely issue for me also. I have much more brake dust on my tag wheels than any other axle. Its time for me to R & R the wheels for a thorough examination of the brakes.

I am a big proponent of Tire pressure monitoring systems (TPMS). Its another gauge of whats going on. I recently overloaded a trailer, I knew I was overloaded, I watched the temperature climb on the heavier side of the trailer. I didn't know what temperature the tire would be damaged at, but it did blow out.  I wish I could be more informative as to what the temperature is for failure, but as it is unfolding on the highway, I didn't look at the gauge. The lesson is, don't let it get hotter than the rest. So as a precaution, when I got to my destination I removed my axle bearings and they were toast.

As for guide pins, they should not be greased for the following reasons. If these pins do not exist in a air tight, sealed environment, grease can retain dirt and gum up sooner than a dry environment. Unless your into a R&R on some scheduled basis, I would advise against grease, instead, remove corrosion and make very clean.

The S cam drum brakes on older Semi truck and I'm sure older Newells, are less prone these type of problems, but they have less brake swept area and retains heat more than the disc brakes.