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The Q40312 Spring Washer is a precision-engineered split-type lock washer designed to prevent bolt loosening under dynamic loads and vibration in SINOTRUK Howo heavy-duty trucks. As a premier supplier of genuine Sinotruk howo parts, we offer this spring washer as a direct OEM replacement, manufactured to the original equipment’s stringent specifications. The washer features a helical split design with sharp edges that bite into the bearing surface and the bolt head, providing consistent spring tension and effective resistance to rotational loosening, ensuring long-term reliability under the extreme vibration and dynamic loads typical of heavy-duty trucking.
This spring washer (OEM Q40312) is essential for maintaining clamp load in critical chassis and driveline bolted joints, including suspension arms, crossmembers, and brake components. Its hardened steel construction and precise geometry guarantee consistent locking action over multiple tightening cycles. The Q40312 is built to endure the rigors of long-haul transport, off-road operations, and severe environmental exposure, delivering dependable service over thousands of miles.
OEM direct replacement • Hardened spring steel • Split helical design • Corrosion-resistant finish
The Q40312 Spring Washer, also known as a split lock washer, is a simple yet highly effective anti-loosening device used extensively in the chassis and powertrain of SINOTRUK Howo trucks. Engineered as a direct OEM replacement, this washer guarantees correct inner diameter, outer diameter, and thickness to match the original specification. Manufactured to the highest standards, it ensures a precise fit and reliable locking performance in critical fastening applications.
The washer is produced from high-carbon spring steel that is heat-treated to achieve a hardness of HRC 40–50, providing excellent elasticity and resistance to permanent deformation. The split design creates a sharp edge at the cut, which bites into both the bolt head and the joint surface when tightened, generating a frictional locking force that resists loosening from vibration. The washer’s helical shape also provides a slight spring action that helps maintain clamp load if the joint settles.
This spring washer is essential for preventing bolt loosening, reducing the risk of joint separation and component failure. Its robust material properties and precise engineering guarantee reliable locking over extended service intervals, meeting the rigorous demands of heavy-duty trucking. It is the direct replacement you can trust to keep your SINOTRUK Howo securely fastened.
The Q40312 Spring Washer is specifically designed for SINOTRUK Howo heavy-duty trucks, including Howo A7, T7H, T5G, and many other models. It is used with M12 bolts in a wide range of chassis and driveline applications, including suspension mounting bolts, crossmember attachments, brake caliper brackets, and engine mounts. Its standard M12 size makes it a versatile and essential component for maintaining joint integrity.
This spring washer is suitable for a wide range of operating environments, including long-haul trucking, regional distribution, construction, mining, and agricultural operations. Its hardened steel construction and corrosion-resistant finish ensure reliable locking even under sustained heavy loads, high vibration, and extreme ambient conditions.
When replacing, always verify the inner diameter to match the bolt size (M12) and the outer diameter to ensure proper joint design. The Q40312 is a direct-fit component that simplifies maintenance and restores original locking performance.
Installing the Q40312 Spring Washer is straightforward but requires correct orientation and torque. Place the washer under the bolt head or nut with the split edge facing the bearing surface (the sharp edges should dig into the joint material and the bolt head). The washer should be installed with the split facing in the direction of rotation that prevents the sharp edges from catching during tightening.
Tighten the bolt or nut to the torque value specified in the service manual using a calibrated torque wrench. The spring washer provides additional locking resistance but does not replace the need for proper torque. For applications with extremely high vibration, consider using a thread-locking compound in addition to the spring washer, but ensure the washer remains free to rotate during tightening to avoid false torque readings.
Regular maintenance includes periodic inspection of the washer for signs of corrosion, deformation, or loss of tension. If the washer shows any damage, flattening, or significant rust, replace it during routine service. Washers that have been subjected to multiple tightening cycles may lose their spring effect; replacement is recommended whenever a joint is disassembled. Always use a new spring washer when reassembling critical joints to ensure optimal locking performance.
This washer is engineered for long service life, but proper installation and periodic inspection ensure continued locking effectiveness and joint integrity.
This spring washer is manufactured in an ISO 9001-certified facility using high-quality spring steel sourced from approved mills. The raw material is tested for chemical composition, tensile strength, and hardness to ensure it meets the required grade. The stamping and heat-treatment processes are carefully controlled to achieve the correct hardness and split geometry.
Every washer undergoes 100% dimensional inspection, including inner diameter, outer diameter, thickness, and split gap verification. We also perform hardness testing on random samples to confirm HRC 40–50. The zinc plating thickness is measured and salt spray tested per ASTM B117 to ensure corrosion resistance. The washers are cleaned, deburred, and carefully packaged to prevent damage during transportation.
Our commitment to quality ensures a spring washer that provides consistent locking force, reducing the risk of bolt loosening and joint failure. Backed by a comprehensive warranty, this washer offers peace of mind for fleet operators and owner-operators.
Choose genuine quality for your fastening needs – choose the Q40312 OEM spring washer.
The Q40312 Spring Washer is a small but essential component that prevents bolts from loosening under vibration, ensuring the long-term integrity of critical chassis and driveline joints. Its hardened steel construction, split helical design, and corrosion-resistant finish guarantee reliable locking performance, reducing the risk of joint separation and component failure. It is the genuine solution you need.
By choosing this genuine OEM-quality spring washer, you avoid the risks of bolt loosening, loss of clamp load, and joint failure that can occur with inferior aftermarket washers. It is engineered for long-lasting performance, ensuring that every bolted connection stays secure under the most demanding conditions. The Q40312 delivers the reliability you expect from a genuine SINOTRUK Howo component.
Fleet operators will benefit from reduced maintenance costs, fewer fastener-related issues, and improved vehicle safety. Owner-operators will gain confidence in their truck’s ability to handle heavy loads and rough roads without compromising joint integrity. This spring washer is the dependable choice for professionals who demand the best.
Invest in this OEM spring washer and experience the difference that genuine quality makes. Its proven reliability and engineering excellence make it the smart choice for anyone who values performance and durability. The Q40312 sets the standard for spring washers in heavy-duty trucks.
Order your Q40312 Spring Washer today and ensure every bolted connection in your SINOTRUK Howo remains secure and reliable for miles to come.