1988 GMC K3500 Bore: 3.1563 In.; Position: Front;. 1989 GMC K3500 Bore: 3.1563 In.; Position: Front;. 1990 GMC K3500 w/Single Rear Wheel (SRW) | Bore: 3.1563 In.; Position: Front;. 1991 GMC K3500 w/Single Rear Wheel (SRW) | Bore: 3.1563 In.; Position: Front;.