Eaton Detroit Truetrac Differential 27 Spline 1.15in Axle Shaft Diameter 3.73 & Up Ratio Dana 30The Detroit Truetrac is a helical gear style, limited slip differential that maximizes wheel traction and enhances driving characteristics. Maintenance free, it features smooth, automatic operation in forward and reverse. Its versatility makes Detroit Truetrac the ideal traction solution for almost any type of vehicle. This Part Fits: Year Make Model Submodel 1970 1974 Volvo 142 Base 1971 1972 Volvo 142 E 1974 Volvo 142 GL 1970 1974 Volvo 142 S 1970