drove jammin all of last year x2 truggy 14 gallons .....no problem ever
spider gears (the 4 gears on the 2 pins) use 1 shim
on the outside of the diffs ( over the outdrives ) 2 shims per side
i know it is crazy ..but i never reshimmed it for 14 gallons ..no wear no probs
jammin makes the toughest truck out there .. a bit heavy and outdated ..but cannot be beat for wear and tear .....
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