Axle For 1988 GM 8.5 Inch Truck, 4Wd-28 Spline , C10 33-1/4 Inch Long USA Standard GearUSA Standard Axle for 1988 GM 8. 5 Truck, 4WD 28 Spline, C10 33 1 4 long 6 lug 33. 25 long Fits GM 8. 5 inch GM 4WD truck 28 spline Features and Benefits: 6 lug 33. 25 inch long Fits GM 8. 5 inch in GM 4WD truck 28 spline Details: AAP UDA 4: 50 Axle Nut Included: No Axle Shaft Seal Included: No Axle Type: semi Float Cv Joints Included: No Inboard Spline Quantity: 28 Rust Resistant Coating: No Shaft Length: 33. 25 inch Application Summary: 1988