Dan:
Quote:
When new shoes are installed and/or drums are turned, only a small part of the shoe contacts the drum until enough wear occurs to conform the shoe's friction material to the drum
True.
Also you may have a bad wheel cylinder which will cause pulling.
Back when drum brakes were on 99.9% of vehicles on the road, brake shops has a planning or grinding machine that could change the outer radius of a shoes friction material to conform with a drum that had been turned to a larger radius. This machining of friction material allowed for full contact between the two surfaces, reducing the ill stopping dynamics of miss matched radiuses.
My 2 cents:
Today these machines are not to be found except in a brake shoe museum, scrap heap, or some eccentric obsolete automotive tool hoarder's out building.
The workaround to proper fitting shoes to drums is to not turn old drums, but to install new drums. Or, as Dan said, endure a magical mystery trip every stop resulting in long stop distances, and routine darting left or right willy-nilly until the miss-fitting shoes wear in.
Having driven a Dart with 9" drum brakes back in the early seventies a bazillion miles, the damn things are next to useless as a stopping device. Often when driving close to triple digits (ah to be 20 again), and attempting to aggressively slow down, it was hard to tell the difference between depressing the clutch or brake. Oh, now I remember, stepping on brake made a lot of vibration, clutch no change in noise, and stopping distances were much the same between both pedals. Perhaps this is a bit of an exaggeration, so I just say 9" drums suck in every way possible.
If I had a 9" drum brake A Body today I would avoid as much tight fast moving traffic as possible as I don't think this equipment can be safely driven on today's roads. My opinion is every other vehicle on the road can stop in half the distance even if those 9 inchers are factory fresh.
Take Dan's advice, and install a set of disks, they are cheaper than front end sheet metal.
By the way my 67 Dart came with factory optional K-H disks, and its braking power is close to modern car performance.
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67' Dart GT Convertible; the old Chrysler Corp.
82' LeBaron Convertible; the new Chrysler Corp
07' 300 C AWD; Now by Fiat, the old new Chrysler LLC
