Bachmann Railtruck fix

[g-guage_trains]

Hi, George Schreyer's site on the Bachmann Railtruck said it is susceptible to surging due to the accumulated slop in the driveline. George talked to Barry's Big Trains and Barry says that he has completely reworked the driveline to eliminate the slop and therefore the surging.
Barry, can you tell me the fix?
alanrr