Understanding GM T3 Headlight History + Reason for Springs around the Brake Drums!

A T3 headlight expert explains the history and differences associated with the T3 headlights used in GM cars from 1956 into the ’70’s.

Question

I cannot figure out the point of the large spring wrapped about the outside of the brake drums on my ’57 Belair..they must do something as GM doesn’t waste parts for fun.

This applies to GM cars and others during production 50′ and 60’s.

Answer:

Jim…..Danchuk carries them and says this: This handy little item absorbs resonance that would otherwise be transferred back into the car. Replace this spring when rebuilding the brakes. For use with original type drums only. Will not work with aftermarket replacement drums.

That coincides with my understanding that understand that they are for noise reduction only. Supposed to cut down the oscilations of the drum to reduce squeeling and chattering. They may or may not be on the rear drums?

Mike says he is right. The spring “absorbs” the resonance of the brake drum. If it wasn’t there you might hear a ringing noise from the drum. That’s why when you cut a drum on a brake lathe you wrap the leather belt around it.