taylorra:In addition to the above and the Factory listed "fixes" for the front/rear GGI pony trucks; you might see if a newer addition to the list of "fixes" might help.
When Lionel brought back the GGI in MPC days, they used the "fast-angle wheels" on the pony trucks. This caused a "Waddle" of the truck(s) as it traveled down the track.
Two "fixes" were used to help eliminate the problems. One was to change out the Fast-angle wheels with the older type of "flat-tread wheels" as was used in the Corporation days. The other, was the use of two washers and a spring over the trucks around the truck guide to put additional pressure on the truck to the rail. A large phenolic washer was used against the truck with the spring and then a brass washer was used to keep everything from slipping up into the frame
I would also check the wheels of the current trucks on their axles. Units that have had much run time without periodic lubrication, could had enlarged axle holes and cause the wheels to wobble about the axle and could cause derailments. Hope this helps. Dennis M.
