Spring in Georgia means puddles that last for days and red clay that sticks like it has a grudge. Driving through all of it is the best part of owning a basher. The worst part is the truck that comes back a week later with crunchy bearings, rusty screws and a steering servo that buzzes at you because you parked it wet.
The fix is not fancy. It is a cleanup routine you do the same day, plus a little knowledge about what "waterproof" actually covers. This guide uses the cleaning steps from Traxxas and the wet-conditions section of an ARRMA owner manual, with notes from what we see on the repair bench after a rainy weekend.
The Short Answer
After a mud run, pull the battery, sling the water out of the tires, rinse with low-pressure water (never a pressure washer), blow it dry with compressed air, spray water-displacing light oil on the bearings, drivetrain and fasteners, give the motor its own clean and re-oil, and let it dry overnight before storing.
- "Waterproof" means the electronics, not the bearings, screws and pins. Those rust if you skip cleanup.
- Do it the same day. Mud keeps water pressed against metal.
- Skip salt water, keep the transmitter dry, and gear down for deep mud.
- Check bearings by spinning them after every wet run, and replace any that stay gritty.
1. What "Waterproof" Really Means on an RC Car
Most modern bashers advertise waterproof electronics. Traxxas says most of its RC models feature waterproof electronics, and it markets the Rustler 4X4 VXL's electronics as waterproof, for example. That is great. But the ARRMA manual says it plainly: the vehicle "is not completely waterproof and your vehicle should NOT be treated like a submarine." Its mechanical parts are water-resistant and "should not be submerged."
What gets hurt by water
The ARRMA manual warns that bearings, fasteners and other metal parts "will be susceptible to corrosion" if you skip maintenance after wet runs. That matches our bench: rusty wheel bearings, seized hinge pins and crusty screws that strip when you try to remove them. Motors take a hit too. The same manual warns that running a wet motor at high speed may rapidly damage it.
Things that are never waterproof
- Your transmitter. The ARRMA manual notes most transmitters are not water-resistant. Keep it out of the rain.
- Salt water. It is conductive and corrosive. Do not run in it, period.
- Your LiPo. ARRMA says caution should be taken with LiPos in wet conditions, and the Rustler 4X4 VXL owner's manual goes further: do not use LiPo batteries in wet conditions. Follow your vehicle and battery maker's rules. A dented or cracked pack should never go near water.
Before you go splashing
Gear down. For heavy loads like mud and deep water, ARRMA's manual says to alter the gear ratio with a smaller pinion or a larger spur gear. Extra load means extra heat. Put the body on, check that the receiver box lid is fully seated, and bring a towel, a cheap brush and a can of water-displacing oil in the car.
2. The Same-Day Cleanup, Step by Step
Do this before you do anything else, including dinner. The longer wet mud sits, the more time water has to work into bearings and the harder clay gets.
| When | Job | Why |
|---|---|---|
| At the mud hole | Spin the tires in short bursts, battery out, dry the battery contacts | Gets water out of tires and connectors before it settles |
| Same day | Wheels off, rinse with low-pressure water, compressed air dry | Mud holds water against bearings and hinge pins |
| Same day | Water-displacing light oil on bearings, drivetrain and fasteners | Stops rust before it starts |
| Overnight | Leave it somewhere warm with the body off | Water and oil keep dripping for hours |
| Next session | Spin-test bearings, check the motor and gear mesh | Catches damage while it is still cheap |
At the puddle
- Sling the water out. ARRMA's method: body off, truck upside down, hands clear, and a few short bursts to spin water out of the tires. The Traxxas manual also says to spin the tires at high speed to sling the water out.
- Battery out. Our habit is to wipe the pack and its connector dry before it goes back in the bag.
- Knock off the big chunks with a brush while the mud is still soft.
At home: wash
- Wheels off. Traxxas says to remove all four. Packed mud can unbalance them and cause vibration.
- Brush and pre-soak. On a waterproof vehicle, Traxxas suggests an all-purpose cleaner and a brush on the chassis, with a soak for stubborn buildup.
- Rinse gently. Use a garden hose, and ARRMA says to avoid spraying the bearings and drivetrain directly. The ARRMA and Traxxas manuals both say never to use a pressure washer.
- Cover the wheel breather holes when you rinse the wheels, so the tires do not fill with water.
At home: dry and protect
- Blow it dry with compressed air, paying attention to hinge pins, bearings and steering parts. Wear eye protection.
- Wipe up what the air does not get.
- Oil the metal. The Traxxas manual says to spray all the bearings, drivetrain and fasteners with WD-40 or a similar water-displacing light oil, and the Traxxas cleaning guide adds drive cups and other exposed metal. A light coat is enough; wipe off the excess so it does not collect dirt. ARRMA says not to spray the motor with lubricant; it gets its own care below.
- Let it drip. Leave it somewhere warm with the body off overnight. ARRMA notes water and oil can keep dripping for hours.
3. Bearings, Motors and Long-Term Waterproofing
Cleanup stops most damage. These habits catch the rest, and they keep your truck ready for the next storm.
Check the bearings
Pull a wheel and spin the axle. FMS Hobby says it should feel "fluid and silent." Gritty or notchy means dirt is in the races. Surface rust or milky grease means water got in. Clean and re-oil the ones that still spin freely, and replace any that stay rough after cleaning. RC Car Action adds a warning: never use a water-based cleaner on bearings.
Seals and grease for wet rigs
If your truck sees water every week, run rubber-sealed (2RS) bearings everywhere you can. They keep out more water than metal shields. For crawlers and trail trucks that sit in creeks, FMS suggests marine grease in the bearings, packed to about a third full so it does not push past the seals.
Motor care
After wet runs, the ARRMA manual says to clean the motor with an aerosol motor cleaner and re-oil its bearings or bushings with lightweight motor oil, and the Traxxas manual likewise says to clean the Velineon motor's bearings and lubricate them with light oil. Do not try to dry a wet motor by running it hard.
Your next-session check
- Spin every wheel and listen for grit.
- Check the gear mesh and the spur for packed mud.
- Look for rust on screws, hinge pins and the steering linkage.
- Confirm the servo centers without buzzing.
- Check the motor temperature after the first pack. Hotter than normal can mean drag from a dirty drivetrain.
Conclusion
Mud runs are what bashers are for. The difference between a truck that lasts years and one that rusts out by summer is about twenty minutes after every wet session: water out, battery out, gentle rinse, air dry, light oil on the metal, a quick motor clean, and a night somewhere warm.
If your truck is already crunchy, bring it to our Cumming showroom and the repair bench will take a look. You can also shop sealed bearings and other replacement parts, browse the tools that make cleanup faster, or contact the shop with questions.
Gear Mentioned in This Guide
Traxxas 1/10 Rustler 4X4 VXL
Traxxas waterproof electronics. The bearings and metal parts still need care after a wet run.
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Pro Boat Marine Grease, 5 oz
For bearings on trucks that live in puddles. A little goes a long way.
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Traxxas Rubber-Sealed Ball Bearings 8x16x5mm (5118)
Rubber-sealed bearings keep out more water than metal-shielded ones.
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5x10x4 Rubber-Sealed Bearings MR105-2RS (10 pack)
Cheap insurance when a mud season finally kills a set.
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Traxxas Speed Bit Master Set (8710)
Drivers for pulling wheels, body mounts and the battery hold-down fast.
Shop nowFrequently Asked Questions
Can I wash my RC car with a hose?
Yes, with low pressure, after removing the battery and wheels, and cover the wheel breather holes. Never use a pressure washer; the ARRMA and Traxxas manuals both warn against it.
Is it OK to use WD-40 on an RC car?
Yes. Traxxas tells owners to spray WD-40 or a similar water-displacing light oil on the bearings, drivetrain, fasteners and exposed metal parts such as drive cups after a wet run. Use a light coat, wipe off the excess, and keep it off the body.
My RC car is waterproof. Do I still need to clean it?
Yes. Waterproof usually refers to the ESC, servo and receiver. Bearings, screws, pins and drive parts can still rust, and manufacturers like ARRMA say the mechanical parts are only water-resistant and should not be submerged.
Can I drive my RC car in the rain?
A vehicle with waterproof electronics can handle rain, puddles and wet grass. Keep the transmitter dry, follow your manual's LiPo rules (Traxxas says not to use LiPo in wet conditions), avoid salt water, gear down for heavy mud and do the full cleanup afterward.
How long should my RC car dry before I store it?
Let it dry overnight in a warm place with the body off and the battery out. Water and oil can drip out of parts for hours, and sealing a damp truck in a bag or box speeds up rust.
Does mud damage brushless motors?
Mud and water add load and heat. ARRMA warns that running a wet motor at high speed may rapidly damage it. Gear down for mud, clean the motor with motor cleaner afterward, and re-oil its bearings or bushings with light motor oil as the manual recommends.
