ZF 0636.302.612 SCREW PLUG for WG92/WG98 | OEM Genuine Part

Overview

The ZF 0636.302.612 SCREW PLUG is a critical sealing component engineered for the WG92 and WG98 series transmissions. This OEM genuine part, identified by SKU 0636.302.612, is installed directly into the 4660101023: TRANSMISSION HOUSING to provide a leak-proof seal at fluid access points. It functions as a primary closure for lubrication and hydraulic circuit ports, ensuring that transmission oil remains contained under high pressure and thermal cycling. Without this precision-machined plug, the integrity of the entire hydraulic system is compromised.

Symptoms of Failure

When the ZF 0636.302.612 screw plug wears out or becomes damaged, operators will notice specific performance issues. Look for these failure symptoms to diagnose a failing part:

• Transmission fluid seepage around the housing: Visible oil droplets or wet spots forming near the plug location on the 4660301058: HOUSING indicate a compromised seal.
• Intermittent gear engagement hesitation: A slow loss of hydraulic pressure due to a leaking plug can cause delayed clutch pack engagement, especially under load.
• Low fluid level warnings without external damage: If the transmission repeatedly shows low oil but no major leaks are visible, the screw plug may be allowing slow vapor or fluid loss.
• Contaminated oil from external debris ingress: A cracked or stripped plug allows dirt and moisture to enter the system, leading to accelerated wear on internal components.

Technical Specifications

Compatibility

This screw plug is specifically designed for ZF’s heavy-duty transmission families. It is a direct fit for the WG 92 Series and WG 98 Series, which includes models such as the WG180, WG200, and WG210. The plug also interfaces correctly with the 0631306174: CYLINDRICAL PIN used for alignment in the same assembly. For applications requiring a different thread pitch, consider the 0750100022: SCREW PLUG as an alternative variant.

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