Futaba S-C400 Low Profile Digital Servo PWM/S.BUS2 8kg 0.08s 4.8V - 7.4V FUT05102742-3

Overview

The Futaba S-C400 Low Profile Digital Servo is a premium surface servo designed specifically for RC car applications, delivering exceptional performance in a compact, lightweight package. This high-voltage digital servo supports both standard PWM control and the advanced S.BUS2 protocol, making it an ideal choice for serious RC car enthusiasts in the UK looking to upgrade their steering control systems. Whether you're running a touring buggy, drift car, or competitive racing setup, the S-C400 combines Futaba's renowned engineering excellence with practical features that make a real difference on the track or bash course.

Built to exacting standards by Futaba, a company that has been leading the way in radio control since 1962, this servo represents the perfect balance between performance and practicality. The low-profile design means it fits seamlessly into modern RC car frames without compromising on torque or speed, whilst the digital circuit architecture ensures smooth, precise control that responds instantly to your radio inputs. For UK RC car enthusiasts seeking a dependable servo that won't let them down during competitive events or weekend bashing sessions, the S-C400 stands out as a genuinely professional-grade choice.

At just 43 grams and measuring only 40.5 × 20.0 × 25.4 millimetres, this servo is engineered to sit low in your chassis, helping to maintain a lower centre of gravity for better handling characteristics. The combination of metal gears, coreless motor technology, and programmable S.BUS2 functionality makes the S-C400 a servo that grows with your RC car hobby, offering features that can be unlocked as you develop your skills and understanding of servo tuning.

Key Features

• S.BUS2 Programming Capability — The S-C400 supports full S.BUS2 programmability, allowing you to fine-tune servo response, centre point, speed ramps, and other parameters directly from your Futaba transmitter without needing external software or computer connections, which is invaluable for optimising performance during competitive racing.
• Dual Control Protocol Support — Whether your radio system uses traditional PWM signals or the more advanced S.BUS/S.BUS2 protocol, this servo will work seamlessly, giving you flexibility when integrating it into existing setups or upgrading your entire RC car UK radio gear.
• Exceptional Speed Performance — With a transit speed of just 0.08 seconds per 60 degrees at 7.4 volts, the S-C400 delivers lightning-fast response that translates to more precise steering inputs and quicker directional changes on the track, which is critical in competitive touring buggy racing.
• Strong Torque Output — Rated at 8.0 kilogram-force centimetres at 7.4 volts (or 111.1 ounce-force inches for users preferring imperial measurements), this servo generates sufficient force to handle aggressive steering inputs without binding or stalling, even during high-speed cornering manoeuvres.
• Low-Profile Form Factor — The compact 40.5 × 20.0 × 25.4 millimetre case is specifically designed to fit into low-slung RC car chassis designs, enabling engineers and builders to optimise weight distribution and suspension geometry without worrying about servo clearance issues.
• Metal Gear Construction — The servo features metal gears throughout the drivetrain (specifically 2-4 metal gears with an aluminium final gear), ensuring durability and longevity even under the stresses of competitive racing, practice runs, and the occasional crash impact.
• High-Voltage Operation — Rated for operation between 4.8 and 7.4 volts, with an expanded operating range of 4.0 to 8.4 volts, the S-C400 gives you the flexibility to run different battery configurations and still enjoy optimal performance, though dry batteries are not recommended for this servo.
• Coreless Motor Design — The coreless motor technology reduces moving mass and increases responsiveness, translating to snappier steering feel and more direct feedback when piloting your RC car through technical corners or racing lines.
• 25-Tooth Spline Interface — The standard 6-millimetre diameter 25-tooth spline is the industry standard for modern RC car servos, ensuring compatibility with a vast range of horns, linkages, and steering components available throughout the UK RC market.
• Lightweight Package — At just 43 grams (1.51 ounces), the S-C400 contributes minimal unsprung weight to your RC car, helping to maintain suspension responsiveness and overall handling balance, which is particularly important in touring buggy and drift car applications.

Technical Performance

The Futaba S-C400 represents a significant step forward in surface servo engineering, combining cutting-edge digital circuitry with time-tested Futaba reliability. The servo utilises a coreless motor paired with a sophisticated digital control system that continuously monitors and adjusts performance 300 times per second, ensuring that your steering inputs are executed with exceptional precision and consistency. The metal gear arrangement, featuring 2-4 metal gears with an aluminium final gear, is engineered to withstand the rigorous demands of competitive RC car racing whilst maintaining the smooth operation and minimal backlash that serious drivers demand. At 6.0 volts, the servo delivers 6.6 kilogram-force centimetres of torque with a transit time of 0.10 seconds per 60 degrees, which is more than adequate for most RC car applications. However, when powered by the full 7.4 volt operating voltage, performance jumps dramatically to 8.0 kilogram-force centimetres of torque and an impressive 0.08 second response time, making this servo suitable for high-speed racing scenarios where every millisecond counts. The servo accepts both PWM and S.BUS/S.BUS2 signal formats, with the S.BUS2 capability opening up advanced programmable features including rate adjustments, trim offsets, and response curve customisation. The compact low-profile design measures just 40.5 × 20.0 × 25.4 millimetres, making it ideal for modern touring buggy frames and other applications where vertical space is at a premium. With a weight of only 43 grams, the S-C400 adds minimal mass to your RC car, helping to preserve the suspension dynamics and handling characteristics that you've tuned so carefully. The servo will operate safely between 4.0 and 8.4 volts, though the rated voltage range of 4.8 to 7.4 volts represents the optimal operating window where full specifications are guaranteed. This flexibility means you can run the servo on 2S or 3S LiPo battery configurations without modification, making it compatible with virtually all modern RC car setups available in the UK market today.

What's in the Box

• 1 × Futaba S-C400 Low Profile Digital Servo
• Servo horns (multiple options for different linkage configurations)
• Mounting hardware (screws and brackets for standard RC car chassis installation)

Frequently Asked Questions

• Is the Futaba S-C400 suitable for beginners to RC car racing? — Yes, the S-C400 is appropriate for hobby-level RC car users, though its advanced programmable features via S.BUS2 mean that it grows with your skill development; beginners will appreciate the straightforward PWM compatibility, whilst experienced competitors will unlock the full potential through programmable customisation.
• What battery voltage should I use with this servo? — The S-C400 is rated for operation between 4.8 and 7.4 volts, which means it works perfectly with both 2S LiPo (7.4V nominal) and 3S LiPo (11.1V nominal, though you would need to regulate it down) battery packs; however, the 7.4 volt configuration delivers optimal performance with the fastest response time of 0.08 seconds per 60 degrees.
• Can I use this servo with my existing PWM radio system? — Absolutely; the S-C400 fully supports traditional PWM control signals, so it will drop into any RC car setup currently using standard servos without any compatibility issues or modifications required.
• How does the S-C400 compare to other low-profile servos? — The S-C400 distinguishes itself through its combination of S.BUS2 programmability, metal gear durability, coreless motor technology, and the backing of Futaba's 60+ year reputation in RC engineering; the 0.08 second response time at 7.4 volts is competitive with premium servos costing significantly more, whilst the 8.0 kilogram-force centimetre torque rating provides genuine power for aggressive steering inputs.
• Is this servo waterproof? — Whilst the S-C400 is a robust servo suitable for outdoor RC car use, it is not specifically rated as waterproof; you should avoid submerging it or exposing it to sustained water spray, though normal racing conditions and light rain exposure should pose no problems.
• Does the S-C400 come with mounting brackets? — Yes, the servo includes mounting hardware suitable for standard RC car chassis, though you may need to purchase additional servo horns or brackets if you're adapting it to unusual mounting configurations in your specific vehicle setup.
• What is SR and UR mode mentioned in the specifications? — These refer to Futaba's Steering Response (SR) and Velocity Response (UR) programmable modes, which allow you to fine-tune how the servo responds to transmitter inputs; these features are accessed through S.BUS2 when paired with a compatible Futaba radio system.
• Why is there a note about no dry battery use? — The S-C400 requires regulated power delivery from a quality LiPo battery pack; dry batteries cannot provide the consistent voltage necessary for proper servo operation and longevity, potentially causing erratic behaviour or damage to the internal circuitry.

Why Buy from RC Model Shop?

RC Model Shop is a trusted UK RC retailer and authorised dealer for all the brands we stock, including Traxxas, ARRMA, Losi, FTX, Hobbywing, Spektrum and more. Based in Walsall, we have a physical store where customers are welcome to come in, view products and purchase in store. Whether you are a seasoned competitor, a weekend basher, or just discovering the world of RC for the first time, our team of experienced RC enthusiasts is here to help you find the perfect setup and provide ongoing support. Order the Futaba S-C400 Low Profile Digital Servo PWM/S.BUS2 8kg 0.08s 4.8V - 7.4V FUT05102742-3 today with confidence, knowing you are buying from an authorised retailer with genuine products, expert knowledge and a commitment to customer satisfaction. Shop online or visit us in Walsall — we look forward to helping you get the most out of your RC experience.