Best Small Differential For Go Kart: Compact Gearbox Options

#1 · Best Overall

1. WPHMOTO Gear box

Best for: Simple electric gearbox swaps.

Why it ranks #1: This standalone 16T gearbox has a 9.5:1 ratio and is listed for 48V to 72V motors, directly matching common electric go-kart drivetrain needs.

A 9.5:1 ratio and 16-tooth transmission make the WPHMOTO gearbox a compactly specified choice for an electric go-kart or tricycle drivetrain. Its stated 48V–72V motor range helps buyers screen electrical compatibility, while the single-gearbox package suits replacement work where the rest of the axle assembly is already in place.

The listed 16T gearbox and 9.5:1 ratio give builders two key transmission details to check against an existing electric setup. WPHMOTO states compatibility with 48V to 72V motors, covering several common electric vehicle configurations listed for go-karts, ATVs, and quads. The metal construction is described as high-strength, wear-resistant, and rust-proof. Because the package contains one differential gearbox, installation planning must account for the remaining drivetrain components separately.

Skip it if you need an axle, hubs, or motor bundled with the gearbox; this listing includes one differential gearbox only.

Choose this for an electric go-kart, ATV, or quad project that needs a replacement differential gearbox and uses a 48V–72V motor. It is a component-level purchase, so plan separately for the axle and other drivetrain parts.

Listed on Amazon as: Universal Electric Tricycle Rear Axle Differential Gearbox 16-Tooth Transmission Assembly for Go Kart ATV Quad UTV

#2 · Torque-Focused Gearbox

2. Kemblawolf Gear box

Best for: 48–72V electric drivetrains.

Why it ranks #2: Its 16-tooth output gear and 9.5:1 ratio suit electric go-karts, with stated compatibility for 48V to 72V motors and rugged metal construction.

A 9.5:1 gear ratio gives the Kemblawolf gearbox a clear torque-oriented specification for 48V–72V electric go-karts and utility vehicles. Its 16-tooth output gear provides a defined sprocket detail, helping builders assess how this rear transmission assembly fits into an electric drivetrain plan.

The listed 48V–72V motor compatibility narrows the intended electrical application and helps buyers screen their build before installation. Its 9.5:1 ratio is presented for torque and acceleration in off-road or utility use, while the 16-tooth output gear supports a specific sprocket-based transmission setup. The metal construction is described as high-strength and rust-resistant, a useful material detail for a gearbox intended for vehicle applications.

Skip it if you run a 36V motor or need a complete axle kit; this listing is a gearbox assembly for 48V–72V applications.

This gearbox suits electric go-kart, tricycle, ATV, UTV, or quad builders whose motor falls within the stated 48V–72V range. Check the drivetrain’s sprocket and installation requirements, since the listing describes a transmission assembly.

Listed on Amazon as: 16-Tooth Differential Gearbox for Electric Tricycle, Go Cart, Rear Axle Transmission Assembly 9.5:1 Gear Ratio – Fits 48V–72V Motor Go Kart, ATV, UTV, Quad – Heavy Duty Metal Construction

#3 · Broad Voltage Range

3. 91.SCS Gear box

Best for: Torque-focused electric gearboxes.

Why it ranks #3: The 16T gearbox offers a 9.5:1 reduction and its title lists 36V, 48V, 60V, and 72V motor use, though feature text specifies 48V–72V.

The 9.5:1 reduction ratio is the central feature of this 91.SCS differential gearbox, with the listing linking it to torque, climbing, and low-speed control. Its 16-tooth spline input gives electric go-kart and tricycle builders a specific drivetrain connection detail to assess before selecting a replacement gearbox.

The 9.5:1 reduction is described as reducing motor speed while increasing torque, a configuration aimed at smoother starts and controlled low-speed operation. The 16T spline input is presented as a power-transfer connection for many electric motor drivetrains, helping buyers compare it with their existing setup. The listing states compatibility with 48V–72V electric motors and identifies applications including electric tricycles, go-karts, ATVs, quads, UTVs, and golf carts.

Skip it if you need the motor and axle included; this listing supplies a differential gearbox, while the Kemblawolf 72V 1500W kit includes a motor and axle components.

This gearbox suits electric vehicle builders seeking a 9.5:1 reduction and 16T spline input for a 48V–72V drivetrain. Check the existing input connection and plan separately for the motor, axle, and other assembly components.

Listed on Amazon as: 16T Rear Axle Differential Gearbox Transmission 9.5:1 for Electric Tricycle Go Kart ATV Quad UTV Golf Cart – 36V 48V 60V 72V Motor Drive Gear Box

#4 · Axle-Specific Housing

4. YC Yier Gear Housing

Best for: DIY axle-housing rebuilds.

Why it ranks #4: This housing provides a defined 11:38 ratio, 20mm axle diameter, and 6T spline, but the listing says it fits only the brand's CV axle and drive shaft.

An 11:38 gear ratio paired with a 20mm axle diameter gives this YC Yier rear gear housing a defined starting point for DIY drivetrain rebuilds. Its stated 6T spline and M12 thread details help builders assess the connection requirements before planning a go-kart or quad assembly.

The package contains one gear housing, rather than a complete axle kit, so it suits a project where the builder is sourcing the remaining drivetrain parts separately. The 20mm shaft diameter and 6T spline provide concrete dimensions for planning the axle connection, while the 11:38 ratio identifies the housing’s gearing. YC Yier states that it fits only its own CV axle and drive shaft, making that compatibility restriction a key installation boundary.

Skip it if you need a complete axle assembly or want to use a different brand’s CV axle; this package contains only the housing.

Choose this for a DIY go-kart or quad rebuild when a housing is the needed component and the matching YC Yier CV axle and drive shaft are part of the plan. It is not a complete rear axle kit.

Listed on Amazon as: Go Kart Rear Differential Axle Drive Shaft Gearbox Housing Transmission Case CV Axle Housing Gear SetFor DIY Rebuilds Vehicles ATV UTV 4 Wheelers Quad Off-Road Buggy Golf Cart Motorcycle parts

#5 · Complete Axle Hardware

5. YC Yier 32-inch Axle Kit

Best for: 25mm axle-and-hub builds.

Why it ranks #5: The kit includes two short axles, brake discs, and 4-stud hubs; its 25mm shaft and 110mm hub bolt spacing make it a larger assembly, not just a small gearbox.

A 25mm drive axle and 110mm four-stud hub spacing give this YC Yier kit practical mounting dimensions for a go-kart or trike rear-end build. The package also lists two short axles and two brake discs, so buyers can plan around more than the central axle alone.

The kit’s 6-tooth spline identifies the drive connection, while the 25mm axle diameter helps builders evaluate the shaft against their chassis and drivetrain requirements. Its four-stud hubs use 110mm bolt spacing, a useful wheel-mounting measurement for planning assembly. Two brake discs and two short axles are included, and the stated 190mm disc-rotor outside diameter gives another concrete dimension to consider during brake integration.

Skip it if you need a motor or gearbox included with the axle; this package lists axle, hubs, and brake discs instead.

This suits builders assembling a go-kart, golf cart, ATV, buggy, or trike rear end around a 25mm axle and 110mm four-stud hubs. Confirm the project’s mounting and brake dimensions against the listed measurements.

Listed on Amazon as: Heavy Duty 32 inch Rear Differential Axle Kit 6T 25mm Drive Shaft with 4 Bolt 110mm Wheel Hubs Flange for Go kart Golf Cart ATV Quad Buggy Tricycle Drift Trikes

#6

6. TJHSM 40-inch Axle Kit

Best for: Motor-and-axle replacements.

Why it ranks #6: This is a complete 40-inch rear axle and motor kit rather than a standalone differential; listed 48V motor options are 500W and 1000W.

The 40-inch rear axle kit combines a differential axle with a brushless motor, giving electric go-kart and golf-cart builders a bundled replacement direction. The listing provides separate 48V 500W and 48V 1000W motor performance figures, helping buyers compare the stated operating profiles for their project.

The kit is described as a direct replacement, which can simplify installation planning when replacing a corresponding rear assembly. Its 40-inch axle length gives builders a concrete packaging dimension, while the listed 9.5:1 ratio and motor-speed figures help frame drivetrain selection. The 500W option is listed at up to 13mph and the 1000W option at up to 20mph; these are distinct configurations, not a single shared performance specification.

Skip it if you need only a gearbox or a 72V motor assembly; this kit’s listed motor configurations are 48V 500W and 48V 1000W.

Consider this for a go-kart, golf cart, or ATV replacement project needing both a 40-inch axle kit and motor. Select against the stated 500W or 1000W configuration figures, since performance differs between them.

Listed on Amazon as: 40 Rear Axle Kit Electric Brushless Differential Motor 3 Stud Hub Replacement for go Kart Golf cart ATV 5 Wheels

#7

7. Kemblawolf 72V Axle Kit

Best for: 72V high-output axle builds.

Why it ranks #7: Its 72V, 1500W brushless motor and 40-inch axle make it a full high-power conversion assembly, the least suitable fit for someone seeking only a small differential.

A 72V, 1500W brushless differential motor rated up to 4800 RPM gives this Kemblawolf kit a clearly specified powertrain for electric vehicle conversions. It arrives with a 40-inch rear axle shaft and dual half axles, making it a bundled option for builders planning a complete rear-drive assembly.

The 1500W motor’s stated 3.3Nm torque and 4800 RPM rating help define its intended high-speed build profile. A 40-inch (1020mm) axle shaft and dual rear half axles are included, giving conversion projects a matched set of major rear-drive components to plan around. The listing also identifies four-stud wheel hubs for standard four-lug wheels, which helps narrow wheel-mounting considerations during assembly.

Skip it if you need a 48V-only motor assembly; this kit specifies a 72V 1500W motor, while Kemblawolf’s 16-tooth gearbox is listed for 48V–72V motors.

This kit fits a conversion or replacement project seeking a 72V motor, rear axle shaft, half axles, and four-stud hubs together. Account for its 40-inch axle length and 72V motor specification when planning the vehicle.

Listed on Amazon as: 72V 1500W Electric Brushless DC Differential Motor with 40" Rear Axle Shaft Kit and 4-Stud Wheel Hub for Go Kart ATV Quad Drift Trike Mini Bike Golf Cart Tricycle Buggy 4 Wheelers Rear Axle Assembly