Well i think all the HL gearboxes are the same.... Funny thing is on some of my tanks i can turn the drive wheel and the gear box seems to turn easy and keep spinning and on other tanks well it's very hard to turn the drive sprocket and it don't spin easy at all........ So my next conclusion is the gear boxes with the black motors have stronger motor magnets making them harder to turn where as the white capped motors have weaker magnets making them easy to turn???
Do not know this for sure but it is puzzeling for sure.
And i don't know what it is..

hi shenlonco, have seen 2 models of tranys,
some transmissions have a clutch plastic gear the first plastic gear next to the motor (for me it was the black motor that had it).my white motors did not have the clutch system.
i think the white motors are stronger ?

That's interesting. Does anybody have the KV statistics on the black versus white motors?

D.

that would be just great ! anyone have tested those engines ?

yes James posted it some whare a few weeks ago...the black motors draw more amps.... so we all came to the conclusion if you ran the white motors you would most likely burn out less electronics.

Roger that! The black capped motors were more powerful. [link=http://www.rcuniverse.com/forum/m_5876157/tm.htm]Motor and Gearbox Testing[/link]

Not all HL gearboxes are the same. THe Buldog gearvox has an output shaft that is 1/4"longer