How to Diagnose Faulty Brake Hoses
& True Facts on Original Brake Hoses

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TRUE FACTS ON ORIGINAL BRAKE HOSES

• The average life of a (Rubber) brake hose is six years.

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• Brake hoses deteriorate from the inside as well as the outside.

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• Moisture is absorbed into brake fluid systems through brake hoses.

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• Contaminants in brake fluid act abrasively on the inner wall of brake hoses.

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• The brake hoses reinforcing fabric deteriorates through expansion and heat.

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• High operating temperatures contribute to the deteriorating of hoses.

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• Brake hoses swell with age and this in effect restrict flow.

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• Generally all brake hoses on a vehicle deteriorate at the same rate, so all 
  the hoses should be replaced even if one is found to have problem.

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Brake hoses and its hardware are two of the most neglected areas of brake maintenance. The gradual degradation of these components can contribute to poor braking and annoying squeal. Under heavy usage and age, the original rubber hoses tend to swell when the brakes are engaged, which results in a spongy brake pedal and increased 
stopping distance. 

The most effective way to check for faulty brake hoses is when they are under pressure.

Brake hoses could appear alright but it's when they are subjected to extreme pressure such as in emergency braking that they need to be in good condition to handle stress.

Most braking systems with booster assisted brakes obtain pressures of approximately 
1500 psi.

The best method to test hoses is to have the engine running for maximum boost and have someone pumping the brake pedal while the hoses are inspected.

Visual and by touch inspection

Things to look for in visual inspection are:

1. Cracks in the outer layer of the hose. Hoses may need to be bent for this test.
2. Blisters or bubbles in the hose.
3. Chafe marks from where it has been rubbing against something.
4. Any wet marks where a hose is starting to leak.
5. Any obvious bulging or expansion of the hose.
6. Loose hose mounts or twisted hoses. All brake hoses have two continuous lines of printing on the hose to make it easy for the installer to indicate if the hose is twisted.

Things to look for in inspection by touching:

1. Hard and stiff hoses.
2. Expansion. This should be hardly noticeable.
3. Soft and weak hoses.
4. Cracking and blistering hoses.