RC shock oils play a crucial role in suspension performance, affecting how well your RC car absorbs bumps, handles corners, and maintains traction.
Choosing the right shock oil can improve handling, stability, and durability, but with different viscosities available, it can be tricky to decide which one is best for your setup.
🏷️ RC Shock Oils ⭐⭐⭐⭐⭐
This guide will cover what RC shock oils are, how they work, how to choose the right viscosity, and maintenance tips to keep your suspension in top shape.
Table of Contents
What Is RC Shock Oil?
RC shock oil is a silicone-based fluid used inside oil-filled shock absorbers to control damping. The viscosity of the oil determines how quickly the shock piston moves through the fluid, directly impacting how the car responds to bumps, jumps, and turns.
RC shock oil is measured in:
- CST (Centistokes) – The international standard for measuring viscosity.
- WT (Weight) – Commonly used in RC (e.g., 30WT, 40WT).
💡 CST is a more precise measurement than WT. Different brands may have slight variations in WT ratings, but CST provides a universal viscosity rating.
How Does RC Shock Oil Work?
Inside an oil-filled shock, the piston moves through the oil, creating resistance that controls the compression and rebound of the suspension.
- Thicker oil (higher CST/WT) = Slower piston movement = More damping
- Thinner oil (lower CST/WT) = Faster piston movement = Less damping
The right balance between oil viscosity and shock piston hole size affects:
✅ Handling and Stability
✅ Bump Absorption
✅ Jump Landings
✅ Cornering Grip
Choosing the Right RC Shock Oil
1. Consider Your RC Car Type
Different RC cars require different shock oil viscosities based on weight, terrain, and driving style.
| RC Type | Recommended Shock Oil (CST/WT) | Notes |
|---|---|---|
| 1/10 Scale Buggy | 300-450 CST (25-40 WT) | Balanced damping for off-road tracks. |
| 1/8 Scale Buggy | 450-650 CST (35-55 WT) | Handles rough terrain and jumps better. |
| Short Course Truck (SCT) | 400-600 CST (30-50 WT) | Good for mixed surfaces. |
| Monster Truck | 600-900 CST (45-70 WT) | Heavier cars need thicker oil for stability. |
| On-Road RC | 200-400 CST (20-35 WT) | Lighter oil for quick weight transfer. |
💡 Larger RC cars need thicker oil to handle their weight, while lighter cars use thinner oil for faster suspension response.
2. Adjust for Track Conditions
The track surface plays a big role in determining the right shock oil viscosity.
- Smooth, High-Speed Tracks → Lighter oil (200-400 CST) for quick handling response.
- Bumpy, Off-Road Tracks → Thicker oil (450-700 CST) for better shock absorption.
- Jumps & Hard Landings → Thicker oil (500+ CST) to prevent bottoming out.
- Cold Weather → Oil thickens in low temperatures, so using slightly thinner oil can maintain performance.
- Hot Weather → Oil thins out in heat, so using slightly thicker oil helps keep damping consistent.
How to Change RC Shock Oil
What You Need:
✅ Shock oil (correct viscosity)
✅ Shock pliers or soft grip pliers
✅ Paper towels
✅ Small screwdriver or hex driver
Step-by-Step Guide:
- Remove the Shocks – Unscrew the shocks from the suspension arms.
- Disassemble the Shock – Unscrew the cap and remove the shock shaft and piston assembly.
- Drain Old Oil – Pour out old oil and clean the inside with a paper towel.
- Refill with New Oil – Fill the shock body ¾ full, then slowly move the piston up and down to release air bubbles.
- Let Bubbles Settle – Wait a few minutes until no more air bubbles rise to the surface.
- Reassemble and Close the Shock – Make sure the oil level is correct, and securely screw the cap back on.
- Test Suspension Movement – Compress and release the shocks to check smooth operation before reinstalling.
💡 For balanced suspension, make sure all shocks have the same oil viscosity and are properly refilled.
The video below might be helpful to understand the process
Fine-Tuning Shock Oil for Performance
If your RC car feels too bouncy or too stiff, adjusting the shock oil viscosity can improve handling.
Symptoms & Solutions:
- Car Bounces Too Much → Oil is too thin; use a thicker oil.
- Car Feels Too Stiff → Oil is too thick; use a lighter oil.
- Car Bottoms Out on Jumps → Use thicker oil to slow compression.
- Car Oversteers or Understeers in Corners → Adjust oil weight in front or rear shocks for better balance.
💡 You can also adjust shock pistons (hole size) and spring stiffness for better tuning.
Summary
Choosing the right RC shock oil is essential for better handling, stability, and durability. Whether you’re bashing, racing, or crawling, the right viscosity can make a huge difference in performance.
✔ Use thicker oil (higher CST/WT) for heavy RCs, rough terrain, and better jump handling.
✔ Use thinner oil (lower CST/WT) for smoother tracks, quicker response, and lightweight RCs.
✔ Adjust oil based on temperature, terrain, and driving style.
✔ Regularly change shock oil to maintain performance.
Experimenting with different oil viscosities and suspension settings will help you fine-tune your RC car for maximum performance on any track! 🚗💨
