Rear brake springs breaking

[Milton]

VEHICLE: 2009 Mazda B2300, 2WD, 37,200 miles
ISSUE: developed an intermittent squeal from rear brakes, no change in braking ability
FINDINGS: I got the truck with 7,100 miles on it and the rear brakes have not been touched. I pulled the drum on the left. And found that the "brake shoe adjusting screw spring" (# 8 in the attached diagram) was broken. Pulled the right drum and found the same spring was broken.

So I'm headed out to see if I can get the parts for a complete brake job.

Question 1: Is this unusual?
Question 2: Anyone know the cause?
Question 3: Anything I can do to prevent it?

Thanks.

 

[RonD]

Both springs broke in the same place?
Could be a manufacturing error, so could be a problem on all vehicles using that batch of springs.

If the springs broke at a place where they attach could be sharp edge rubbing them.

Might bet would be the steel in the spring has poor tensile strength from it's manufacturing process, too hot or too cold, and just snapped.

 

[Milton]

Ron thanks for responding. Yes, both springs broke in the coil portion of the spring. I got a complete hardware & spring kit and shoes. I'm waiting for the drums to be resurfaced, slight groove from the loose spring part.

 

[Milton]

Just to close the thread:
Replaced all springs and associated hardware.
Replaced brake shoes just cause I don't want to touch the rear brakes for 90,000 miles.
Turned one drum, replaced the other.

Unable to see any place where the springs would be rubbing against anything. Guess it will be a mystery.

Stops great, no squeal, e-brake works great.

Thanks.