The pin locations are different between the XRT and XRT Ultimate, please make sure you’re using the correct gearing chart. When you change the pinion/spur size, you’ll need to move the motor to the correct location for the new size gears. Do this by removing the 4 bolts under the motor, remove the motor and move the pin locations to the letters in the chart below for whatever ratio you’re using.
Standard XRT
The standard non-ultimate XRT comes stock with a 20 tooth pinion and 50 tooth spur gear. In the box is an optional 23 tooth pinion and 46 tooth spur gear for higher speeds. Speed gearing will reduce battery life, increase motor temps and reduce torque in exchange for higher top speeds. The standard XRT comes with plastic motor mounts and you must use the pin locations in the standard XRT gearing chart below. If you’re using the Traxxas aluminum motor mounts, you’ll need to use the motor pin locations in the XRT Ultimate chart below.
If you’re installing X-Maxx size wheels and tires or paddles on either truck, you’ll want to use the X-Maxx gearing chart and use the X-Maxx pinion/spur ratios. XRT will typically over heat on the larger tires in the XRT ratios.
Standard XRT stock pinion gear: Traxxas 6494X 20T Pinion Gear
Standard XRT stock spur gear: Traxxas 6448R 50T Spur Gear
Standard XRT included high speed pinion gear: Traxxas 6481X 23T Pinion Gear
Standard XRT included high speed spur gear: Traxxas 6447R 46T Spur Gear
XRT Ultimate
The Ultimate XRT comes stock with a 20 tooth machined/hardened pinion and 50 tooth machined/hardened spur gear. In the box is an optional 23 tooth pinion and 46 tooth spur gear for higher speeds. Speed gearing will reduce battery life, increase motor temps and reduce torque in exchange for higher top speeds. The XRT Ultimate comes stock with the Traxxas aluminum motor mount upgrade, make sure you’re using the pin locations in the XRT Ultimate chart below and not the standard XRT chart.
If you’re installing X-Maxx size wheels and tires or paddles on either truck, you’ll want to use the X-Maxx gearing chart and use the X-Maxx pinion/spur ratios. XRT will typically over heat on the larger tires in the XRT ratios.
Ultimate XRT stock pinion gear: Traxxas 6494R 20T Hardened Pinion Gear
Ultimate XRT stock spur gear: Traxxas 6443 50T Hardened Spur Gear
Ultimate XRT included high speed pinion gear: Traxxas 6481X 23T Pinion Gear
Ultimate XRT included high speed spur gear: Traxxas 6447R 46T Spur Gear
