By factory traction bar, I assume you mean the radius rods? According to the "Definitive Firebird and Trans Am Guide 1967-1969", "Every 1967 Firebird rear axle has provisions to accommodate a radius rod beneath each axle tube, but the actual number of rods varied with the application" It also shows Service Bulletin 67-I-38 that has a table indicating the zero, one and two rod applications. Only the 6 cylinder automatic with less than a 3.23:1 ratio had no radius rod. The manual Sprints and V8s got two rods and the rest got one right rod.
