ORIGINAL: NightHawk871
Ok, I might know the answer to this question... I recently took mine apart due to thinking one of the gears were stripped. But I found that the last gear on the trans. (the one that hooks up to the drive wheel) was merley pressed-fit on.... There are no securing fastenres what-so-ever. So the gear was slipping on the shaft....and not allowing movement....Im guessing this is the problem with the HL's pullling to the left or right....the gear on either gearbox is slipping...
That would be a good guess, I know it's a pain, but you mite want to go thru the track drives again and secure those gears to the axel shaft(s)
This can be done in a number of ways..the shafts have a knurled location where the gear is suppose to ride. Clean both shaft and gear with alchol to remove any grease and apply a drop of super glue to the shaft and reinstall the gear, let set. Another way to solve the loose gear issue would be to get the metal gear upgrade and install it. The upgrade replaces all the nylon gears an bushings with metal and brass, be sure to relube the gear drives.
Hope I'm of some help..
Regards
bullyhys