The T - Maxx 2.5 R featured Traxxas ' TRX 2.5 R nitro engine with the Torque - Control slipper clutch on the spur gear .
Traxxas ' TRX 2.5 R nitro engine is a new driveline similar to the Revo 's .
The T - Maxx 2.5 R featured Traxxas ' TRX 2.5 R nitro engine , a new driveline similar to the Revo 's , with the Torque - Control slipper clutch on the spur gear .