0 0 2021 Spicer S172 Rear Differential for a Peterbilt 337 Newly Listed $550 USD (USED) Spicer S172 Ratio: 5.25 Side Gear Splines: 41 W/ Locker: NO Cast#: - ConditionUsedFits To Make(s)PeterbiltFits To Model(s)337Stock Number25918806 MLS Number14067512CategoryDifferentials, Rear Last Updated1/1/2026 LocationSpencer, IA, US Sold ByVander Haag's Inc. (855) 370-___ SHOWNUMBERCall Seller Email Seller Save More Info