Traxxas 3691-GRAY Magnum 272 Gray Gearbox Halves

The Traxxas 3691-GRAY is a left and right pair of gearbox halves for the Magnum 272 transmission, with the idler gear shaft included.

The gearbox halves form the housing that holds the whole transmission together, locating the shafts, supporting the bearings, and setting the gear mesh. Once a half is cracked or a screw boss has stripped, the mesh no longer holds true and wear accelerates straight into the gears. Replacing the housing at that point is considerably cheaper than replacing a chewed-up gearset afterwards.

Typical reasons to fit these are impact damage that has split a case, stripped bosses that no longer clamp the halves together, or a planned rebuild where it makes sense to start with a fresh housing rather than reuse a fatigued one. The included idler gear shaft covers one of the internal parts most likely to be worn by the time the housing needs attention.

Fitment note: these fit the Magnum 272 transmission only and will not fit the Magnum 272R. The two units are not interchangeable, so confirm which transmission your vehicle uses before ordering.

Supplied as a left and right pair. Genuine Traxxas replacement part.