A brake chamber diaphragm is a flexible rubber membrane inside a commercial vehicle's air brake chamber that converts compressed air pressure into linear mechanical motion to apply the vehicle's brakes.

When you step on the brake pedal, air rushes into the chamber, pushing the diaphragm forward, which forces out a pushrod to mechanically engage the brakes.

Common Sizing Types:

Type 12 & 16: Often used on lighter front steering axles.

Type 20 & 24: Common mid-sized configurations for tractors and trailers.

Type 30: The most common size used on heavy-duty rear drive and trailer axles.

Type 36: Extra-large heavy-duty application variant.

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