Check out our stunning new RCMAX BILLET BAJA HD Gearbox. The ONLY precision made Baja gearbox on the market with proper bearing fitments.


This new part has been made specifically at the request of many of our customers to solve existing issues. Featuring the tried and tested 3-piece design for easy removal of the diff and assembly with all the oversize driveshafts on the market.


All the pieces of the case are an extremely precise fit, both dowelled and lipped, to solve alignment/fitment problems. There is zero flex even when running big HP! This precise fit also means there is no grease leakage during use. Finally the rear section is attached with M5 10.9 strength bolts top and bottom for strength.


For all big bore owners, we have allowed more clearance at the back of the engine so there is no more grinding down the front of the gearbox to prevent rubbing the crankcase.


As requested by our customers for easy assembly, the bearing fitments inside the Front two halves of the case are hand push in fitment, so in an ideal world we recommend some mild bearing locker to remove the tiny 0.02mm play that we have left you so that you dont have to use a press. The bearing tolerances however are still tighter and far more consistent than other billet boxes on the market.


Total gearbox weight 245grams.


The gearbox includes a Billet Cap to cover the Layshaft bearing hole and all zinc coated hardware.


Note 1: for baja owners there is a little clash between the plastic rear bulkhead and the gearbox. A chamfer added to the front rear bulkhead inside edges solved the issue. Please accept my apology for this, the price if the box is 10% cheaper than we wanted for our British engineering costs to try offset. (All known Alloy bulkheads on the market clear with no issue which is what we use on our big bore bajas). RPM arms do not work with our diff due to the larger bottom M5 bearing support bolts.


Note 2: For Outlaw Hybrid owners. There is a piece of dremel work required to fit this HD box into the outlaw rear billet “cage” as it’s called. Only on inside hidden edges. If it’s a problem we can happily do this for you of you send us your rear cage piece. All new outlaw kits as of 1-1-2020 fit with no issues.