What Raw Materials Are Used in Manufacturing Electric Running Board Motors? (A Complete Sourcing Guide)
When global B2B buyers evaluate an electric running board motor (power side step motor), they look beyond the shiny metal casing. They want to know what is on the inside. Because these motors operate under the vehicle chassis—constantly battered by mud, road salt, water, and extreme temperatures—the quality of the raw materials determines whether the product will last for ten years or fail in six months.
If you are an automotive parts distributor, an off-road brand manager, or a procurement specialist, understanding the bill of materials (BOM) is crucial. Let’s strip down a premium electric running board motor and examine the exact raw materials required for its production.
1. The Electrical & Magnetic Core (The Powerhouse)
The electrical core converts battery power into mechanical torque. Skimping on these materials leads to motor overheating and weak pedal lifting.
High-Purity Enameled Copper Wire: Used for winding the stator and rotor coils. Premium manufacturers use Grade 200 (Class H) copper wire which can withstand temperatures up to 200°C without melting its insulation layer. This ensures the motor doesn't short-circuit under heavy stall loads.
Cold-Rolled Silicon Steel Sheets: Stamped to form the stator and rotor laminations. High-grade silicon steel (such as 50W470 or 35W300 grade) is chosen for its superior magnetic permeability and low iron loss, which maximizes motor efficiency.
Neodymium Iron Boron (NdFeB) Magnets: For permanent magnet DC or BLDC motors, Rare-Earth Neodymium magnets (typically Grade SH or UH, capable of operating at 150°C-180°C) are utilized. They provide immense magnetic force in a compact size, allowing the motor to generate huge torque to lift heavy side steps.
2. The Transmission & Gearbox (The Muscle)
The gearbox scales up the motor’s rotational speed into massive lifting torque. The combination of materials here must minimize friction while maximizing wear resistance.
Carbon Structural Steel / Stainless Steel (45# Steel / Cr12MoV): The motor's central shaft and the integrated worm screw are CNC-machined from high-carbon or alloy steel. It undergoes induction hardening to ensure the threads do not strip or warp under heavy resistance.
Reinforced Engineered Plastics (PA66+MoS2 / POM): The internal worm wheel (gear) is often injected-molded using Polyamide 66 reinforced with Molybdenum Disulfide, or Polyoxymethylene (POM). This material provides self-lubricating properties, extreme wear resistance, and minimizes gear noise (NVH).
High-Lead Bronze / Brass (optional for heavy-duty): In high-end off-road or military-grade steps, the worm gear is machined from phosphor bronze, offering unparalleled lifespan against heavy impacts.
Specialty Lithium-Based Synthetic Grease: The gearbox is packed with synthetic grease that must maintain its viscosity and lubricating properties across a brutal temperature spectrum—from -40°C in arctic winters to +125°C near the exhaust heat.
3. The Housing & Sealing (The Armor)
Because the motor is completely exposed underneath the vehicle, the exterior materials must form an impenetrable barrier against corrosion and water ingress.
ADC12 Aluminum Alloy: The main gearbox housing is die-cast using ADC12 or A380 aluminum. It provides excellent heat dissipation, structural rigidity, and is naturally resistant to rust.
Fluororubber (FKM) / Silicone O-Rings: To achieve an IP67 or IP68 waterproof rating, all mating surfaces require custom-molded gaskets. Fluororubber is selected for its exceptional resistance to oil, ozone, road grime, and road salt.
Two-Component Polyurethane / Epoxy Potting Resin: Applied via automated dispensing machines at the wire harness exit point to completely seal out moisture and prevent water capillary migration along the wires.
4. Hardware & Electrical Interface
Chromium-Plated / Dacromet Stainless Steel Bolts: Standard steel bolts will rust within weeks underneath a vehicle. Premium motors use Grade 8.8 or 10.9 fasteners treated with Dacromet coatings for superior salt-spray corrosion resistance.
Automotive-Grade Wiring & Connectors (PA66 + Gold-Plated Terminals): The wiring harness uses cross-linked polyethylene (XLPE) jackets that resist abrasion. The plugs are molded from PA66 with internal silicone seals and gold-plated pins to guarantee flawless electrical conductivity over years of exposure.
5. Summary: Why Material Transparency Matters for B2B Sourcing
When sourcing electric running board motors from overseas suppliers, a cheaper price tag almost always means compromised raw materials—such as substituting copper with copper-clad aluminum (CCA), or using low-tier recycled plastics for the internal gears.
At Maiersi, we enforce a strict Material Verification Quality Control process. Every batch of raw silicon steel, rare-earth magnets, and synthetic grease undergoes spectroscopic and thermal testing before entering the automated assembly line.
Are you looking for an OEM/ODM partner that guarantees premium automotive-grade raw materials and 100% traceabilty? Contact our sourcing team today to receive a complete Material Safety Data Sheet (MSDS) and a customized quotation for your market!
