145 through 338 and L-Series Medium Duty Conventional - Rear
145, 165, 185, 238, 238LP, 258LP, 258ALP, 268, 268A, 338 and 338CT (2005-22)
L6 and L7 (2021-22)
Beginning in 2011, springs were redesigned to use an RB type straddle mount eye leaf bushing