ATP Automotive 111501 IFS 8.25 Front Differential Assembly (3.73 Ratio RPO GT4) 4WD Fully remanufactured and reconditioned GM 8.25 front differential No longer available from GM as new, fully remanufactured unit is a better alternative than bench repair or buying used No core program, save time and hassle by not needing to return your old part Replacement for: 1999-06 K1500 Silverado, Suburban, Sierra, Tahoe, Yukon (3.73 ratio GM RPO Code GT4) FOUR WHEEL DRIVE 5 year / 100,000 Mile Warranty