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By Charlie Henry
This is something I found while fixing something else. The chassis and suspension parts of my '57 were sand blasted and painted in preparation for the 1972 Palm Springs Convention. The brake drums were turned and all new brake shoes, hardware, and wheel cylinders were installed. The brakes performed perfectly. However, over the years, a slight, but noticeable pull to the left on initial brake application gradually developed. Since adjusting the brakes had no effect and the pull wasn't severe or getting worse, I learned to live with it.
Recently I replaced the wheel cylinders and converted to silicone brake fluid. Upon stripping the shoes and hardware from the front backing plates, the cause of the brake pull became apparent. In my zeal, 20 years ago, to properly apply black Imron paint, I inadvertently laid the foundation for the pull. Two primer coats and two (possibly three) color coats were applied. The paint was still in excellent condition, except where the brake shoe edges contacted the backing plates.
On both front backing plates, but especially on the right, the shoe edges had worn away the thick paint on the thick paint on the shoe contact pads, creating significant grooves. The grooves on the right were sufficient to prevent those shoes from moving in sync with the left. No matter how often, or carefully, the brakes were adjusted, the left-hand shoes would contact their drum first...causing a slight left pull until the right-hand shoes "broke" out of their grooves and caught up. Grinding the paint on the shoe contact pads down to bare metal, on all backing plates, put my Tbird back on the "straight and narrow."
Now, as part of my annual spring inspection, the bare metal shoe contact pads of the backing plates are checked for wear and rust. If necessary, a small amount (just enough to wet the metal) of white lithium grease is wiped on the contact pads. This inspection and procedure should be performed whenever the brakes are serviced. Over the years, and miles, brake shoes can wear in to the metal backing plate. If grooves can't be sanded or ground smooth, the backing plate should be replaced or…VERY carefully repaired by welding and grinding.
Source: Little Bird Talk - TARTC
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