CTCI Authenticity Chairman
- Weak springs,1957 models should measure approx 27″ from the ground to the center of the tail lamp lens. 1955/56 models should measure approximately 24″ from the center of the tail lamp to the ground. 1955/56 models are less likely to rub and usually have more sever problems if they rub.
- Worn spring mount bolts and bushings.
- Worn anti squeak pads.
- Wrong wheels (max width from inside bead to bead 5″) 1955/56/57
- Wrong wheels sometimes have the wrong off set, which moves the wheel closer to the fender skirts. Refer to the restoration manual for proper wheel identification.
- Wrong tire size ( 6:70 x 15″ for 1955/56, 7:50 x 14″ 1957) the old 70 series are usually too wide and will rub. In addition if your Thunderbird is equipped with 70 series tires they have exceeded their age limitation and should be removed for safety reasons. Radials should be 205/75R15 for 1955/56 models and 205/75R14 for 1957 models, radials are also slightly wider.
- Wrong fender skirts. The 1957 skirts will work on 1955/56 models. The 1955/56 skirts have a shorter locking arm and when installed on a 1957 model the end of the locking arm is closer to the side wall on 14″ tires and will rub.
- Body damage that has been repaired without regard to maintaining proper clearance is a common cause for fender skirt rub.
- Spring pads to axle perches worn and U bolts loose allow the body to shift when making turns. All models have approximately 1″ clearance between the tire and the inner skirt edge at the bottom rear with radial tires. The rear axle cannot be moved enough to effect clearance. The spring perches would have to be relocated. Not practical. The body can be moved ever so slightly on the frame if all body mounts are loose. The body will not usually shift enough to effect clearance.
- If after considering this information and making proper repairs and the rub still exists, I suggest the following: (a) After the above repairs in most cases rear sway bars properly installed will correct the problem. If after all repairs have been completed and sway bars do not correct the problem it is more than likely previous damage that was not properly repaired.