Product Overview

The differential axle side seal, OEM number A1643370159, is fitted to the front differential on the Mercedes-Benz M-Class (W164), GL-Class (X164, including GL450 and GL550), and R-Class (W251, including R350), covering the 2006-2013 production run on 4MATIC all-wheel-drive models. It's commonly paired with the related pinion seal (A1643370059) as part of a complete front differential seal service, since both wear from the same operating conditions and are typically replaced together.

A worn or failing differential seal typically shows up as visible gear oil leaks near the differential, low differential fluid level, or gear noise from accelerated wear caused by low lubrication. GSK Auto manufactures this seal to OEM specification at our Ningbo, China facility, with every unit tested before packing. We supply at wholesale volume with low MOQ and support private label packaging, with our team available to confirm fitment before shipping.

Replacement OEM Numbers

Cross-Reference OEM Number

1643370159, A1643370059, 1643370059, Corteco 01036920B, 0AA409189A, 0734319681

(Confirm against your VIN or chassis code before ordering — these are commonly listed cross-references for this application, not a guarantee of exact fitment for every variant.

What Is a Differential Axle Side Seal?

Function: The axle side seal seals the point where the axle shaft enters the differential case, retaining gear oil inside the differential while keeping dirt and moisture out.

Working Principle: A spring-loaded lip seal maintains contact with the rotating axle shaft, creating a sealed barrier that contains pressurized gear oil while allowing the shaft to rotate freely.

Importance: On a 4MATIC all-wheel-drive platform, a properly sealed differential is essential for maintaining correct gear oil levels and preventing accelerated wear to internal differential components.

Common Failures & Signs: Gear oil leaking near the differential case. Low differential fluid level from a slow leak. Gear noise or whining from the differential due to low lubrication. Visible oil staining on the underside of the vehicle near the front axle.

Key Features

OEM-standard fitment - matches factory dimensions and specification for the A1643370159 application, front differential axle side.

Durable seal material - built to withstand sustained rotation and gear oil exposure.

Excellent fitment - direct replacement, no modification required.

Tested before shipment - every unit checked before packing.

Reliable performance - restores factory sealing and prevents gear oil leaks.

Benefits

Importers - covers front differential seal demand across the ML, GL, and R-Class, often sold alongside the related pinion seal.

Wholesalers - steady demand from a well-established Mercedes-Benz SUV platform family.

Repair Shops - tested unit reduces comeback risk on a differential service.

Distributors - private label packaging available for building a branded catalog.

End Customers - restored differential sealing and protection against gear wear.

Packaging & Shipping

Standard export cartons. Customized packaging available for distributor branding. OEM-style and private label printing on request. Container loading handled directly, with mixed-SKU consolidation for smaller orders. Worldwide shipping to Europe, North America, South America, the Middle East, Africa, and Southeast Asia.

Why Choose GSK Auto

GSK Auto manufactures factory-direct, keeping pricing tied to production cost. This seal is built to OEM specification and tested before packing. We support low MOQ, private label packaging, and worldwide shipping, with our technical team available to confirm fitment before you order.

Call to Action

Sourcing differential axle side seals for the Mercedes-Benz ML, GL, or R-Class? Contact GSK Auto for a wholesale quote, catalog, or OEM/private label cooperation.