AZ9981320136 Inter‑Axle Differential Assembly is a heavy‑duty drive‑axle replacement part built for SINOTRUK HOWO inter‑axle system. All internal gears are manufactured from high‑strength alloy steel, treated by deep‑carburizing and precision‑grinding process. It delivers stable torque distribution and outstanding wear‑resistance, perfectly suited for long‑distance hauling, mining operation and mountain‑road heavy‑load transport. Each differential assembly undergoes strict bench torsion‑load testing and hydraulic‑sealing inspection before shipment to eliminate hidden failure risks. We can provide you with original OEM parts and premium‑quality aftermarket alternatives. A 6‑month quality warranty is available for bulk export orders, ideal for heavy‑truck spare‑part wholesalers, repair workshops and fleet operators worldwide.