R172D557 | Dana Spicer Eaton Differential S23-172D-R5.57 | New Take-Out | 10049265

R172D557 | Dana Spicer S23-172D Differential — 5.57 Ratio — New Take-Out

The R172D557 is a genuine Dana Spicer S23-172D differential head assembly set to a 5.57 ratio with a 23,000 lb capacity. This is a new take-out unit pulled from dealer/OEM inventory with delivery miles only. It was professionally disassembled, inspected, and reassembled in our shop for quality assurance. Commonly found in fleet trucks running super singles. Available from Discount Parts Exchange - DPX in Mansfield, Ohio.

Call DPX to confirm: 419-522-3320.

Highlights

• Model: S23-172D
• Ratio: 5.57
• Capacity: 23,000 lb
• Ring Gear: 17.476" Hypoid Hub Gear (39 teeth)
• Pinion: 7 teeth
• Axle Shaft Splines: 46
• Gear Set Number: 504424
• Build Status: New take-out — inspected and reassembled in-house
• Applications: Fleet trucks running super singles, line-haul and vocational

Gear Data

How to Calculate Gear Ratio: Divide the number of teeth on the ring gear by the number of teeth on the pinion gear (e.g., 39 ÷ 7 = 5.57). This is the standard method used by Dana Spicer.

Cross-References

• Drive Axle Assembly #: 7169441
• Navistar Customer Part #: 3781106C91
• Alternate Numbers: R172D557CF (Core Free) • R172D557EX (Exchange) • DSS172D557EX (Navistar)

Recommended Lubricant

Use Spicer FE 75W-90 Fuel-Efficient Synthetic Gear Lubricant (or equivalent).

Approvals: Dana SHAES 256 Rev E • Dana SHAES 429 • API GL-5 • API MT-1 • SAE J2360 / MIL-PRF-2105E • Detroit DFS93K219.01 • Mack GO-J Plus • Meritor O76-N • Navistar MPAPS B-6821

What’s Included

• (1) Dana Spicer S23-172D differential head assembly — R172D557

Core & Warranty

• Core: New take-out listing (typically core-free). Exchange option available — ask for details.
• Warranty: Sold as-is. No warranty expressed or implied.

Shipping

• Ships via LTL motor freight to verified commercial addresses only
• No residential delivery — forklift or dock required

Image Disclaimer

Photos show the actual product or a representative example. Minor handling marks may be present due to storage or inspection.

Call to Order

Call Discount Parts Exchange - DPX for price and availability: 419-522-3320

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