390DU103 Flange Half | Dana Spicer S400 | Ratio 3.21–3.73 | NOS - Genuine

390DU103 Differential Flange Half — Dana Spicer S400 | Casting 390DU102 | New Old Stock (Surplus)

390DU103 is a genuine Dana-Spicer differential flange half for S400 applications. This is New Old Stock (NOS) surplus—unused OEM inventory that may show light, cleanable surface oxidation from storage. Originally supplied in kit 390KQ102X. Designed for axle ratios between 3.21 and 3.73.

Call to confirm availability: 419-522-3320.

Specs & Features

• Part Number: 390DU103
• Casting Number: 390DU102
• Type: Differential Flange Half
• Condition: New Old Stock (NOS) Surplus
• Manufacturer: Dana Spicer (Genuine OEM)
• Application: Dana Spicer S400
• Kit Reference: 390KQ102X (flange half from kit)
• Ratio Range: 3.21 – 3.73

What’s Included

• (1) Differential flange half — P/N 390DU103 (casting 390DU102)
• Hardware, bearings, and additional components not included

Fitment Notes

• For Dana Spicer S400; verify casting number 390DU102 and dimensions before purchase
• Designed for gear ratios 3.21–3.73; confirm compatibility with your carrier

Image Disclaimer

Photos may show the actual item or a representative example. NOS surplus parts can exhibit light surface rust from storage that typically wipes off.

Warranty Policy

Sold as-is; no warranty or returns. Please verify fitment before purchasing.

Location

Mansfield, Ohio

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