RE: Official HPI MT2 Thread
Why would you consider contacting HPI and asking for replacement gears "whining"? There's a problem with those gears; they know about it, acknowledge it, and will ty to take care of you if you approach them in a calm, mature manner.
I too would like to know the advantages (if any) of these other diff sets.
Some fellow on another thread mentioned a "heavy-duty" set for $100; I asked him for more details, but he never came back.
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