Sometimes cars with oily wheels would get pushed over the hump at a classification yard and they would slip through the retarders as if they weren't there, even though retarders were fully applied. Several cars with dry wheels would then have to go through to burn off the oily film deposited on the retarders before they regained functionality. Such cars would roll to a joint in the bowl without benefit of any retardation. It was interesting to see the dust cloud rise from dusty cars at the joint point, then a very brief pause, then hear a resounding BOOM, especially if MTY. The joint would be made at close to the exit speed of the last tangent retarder, the car having gained speed from when the pin was pulled.

Could it be that some cars of oil trains have oily wheels and could it be that oily wheels could cause a derailment under certain conditions such as curvature and any other conditions? Could a lot of really oily wheels deposit a film on the tracks which would make a derailmlent likely? Supposing there was a truck hunter behind a cut of oily wheelers? What about oily flanges negotiating a curve?

Just a question. Inquiring (possibly retarded) minds want to know.

Here we go again...

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