390KQ100X | Dana Spicer S400 Differential Case Kit | 2.81–2.92 Ratio – New Genuine (NOS)

390KQ100X is a New Genuine (NOS) Dana Spicer differential case kit for S400 axles. This complete kit supports the 2.81–2.92 ratio range and is ideal for heavy-duty front and rear axle applications.

Call 419-522-3320 for pricing and availability.

Kit Contents

• (1) Top Half Differential Case – 390DT101
• (1) Flange Half Differential Case – 390DU109
• (10) Hardware Bolts – HM127

Key Specifications

• Kit Part Number: 390KQ100X
• Manufacturer: Dana Spicer
• Axle Model: S400 Series
• Ratio Range: 2.81 – 2.92
• Condition: New Genuine (NOS)

Fitment Notes

Designed for Dana Spicer S400 front and rear differential configurations. Always confirm your axle model, ratio, and BOM number before ordering.

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Image Disclaimer

Photos show the actual New Genuine (NOS) differential case kit components you will receive.

Shipping / Location

• Ships from our Mansfield, Ohio warehouse (419-522-3320)
• Parcel or LTL options available based on packaging and weight
• Warehouse Bin Location: DPX_OH_BR549_DAN

Heavy-Duty Solutions — Built to Perform. Trusted to Last.
Discount Parts Exchange (DPX) — Mansfield, Ohio — Since 1997