In my case,a stabilization of the base was the obvious correction: I probably should have taken more track out and replaced an entire section of homosote. I opted for a quick fix that has worked for me. Since then I have had no problems at that area of track. The S1 or Q2 were not the problem,they are fine. I have other large 3rd Rail engines that have navigated that area quite successfully such as the Z-8,Big 6,and others.
In retrospect this repair to my little railroad was just like repairing the Pennsy Mainline that ran not too far from my home as a boy. Upkeep.
