here is a complete guide of traxxas rustler, bandit, stampede, and slash gearing options, and how to change and adjust your gears, demonstrated on a traxxas rustler.
Step 1: Tools
you will need: a 9/32 hex wrench, a screwdriver, and 2 if the hex keys that are included with your car.
Step 2: Gearing Options
above I have a chart that shows basic gearing options you can use for higher top speed, or faster acceleration. the bandit comes with a spare 31tooth pinion and an 83 tooth spur. the rustler comes with a spare 28 tooth pinion and an 86 tooth spur (shown in picture). the stampede comes with a spare 21 tooth pinion and a 90 tooth spur. the slash comes with a spare 23 tooth pinion and an 86 tooth spur.
Step 3: Dissasembling Your Gears
first, you'll want to take the wheel blocking your gear guard off. you can put it under your diff case to support your vehicle. next you'll want to remove the to screws holding on your motor guard. you can now take your motor guard off.
to remove the spur gear, use the hex wrench to take off the screw holding on the slipper clutch spring. take the spring off too. you can now remove the spur gear. behind the gear is stuff you won't need to worry about for gearing. to disassemble the gear, unscrew the 3 screws with one of the Allen wrenches provided. you can then remove the slipper clutch pads and the metal thing they are attached to. then you can remove the bearing.
to remove the pinion gear, unscrew the grub screw with the other Allen wrench, then slide the pinion gear off.
Step 4: Reassembling the Gears.
for the spur gear, put the bearing back first. then put the slipper clutch pads but on to their metal holder thing, then screw that back onto the gear. proceed to slide the gear, and then the slipper clutch spring back on to your car. screw the but on all the way, and then loosen it 1/4 to 1/2 of a turn.
for the pinion gear, slide it back on then put in the grub screw.
Step 5: Maintenance
for maintenance, always make sure all screws are tight. especially the one that hold the motor in place.
thanks for viewing, and if you have any questions about information not mentioned, or other rc stuff, please post it in the comments. thanks!