For 1990-2009 cars

### Substandard or Contaminated Brake Fluid

Important:

• | Use only Delco Supreme 11® Brake Fluid, GM P/N 1052535 (Canadian P/N 992667), or equivalent DOT 3 fluid.

• | Do not use power steering or transaxle fluid in the brake system.

• | Do not reuse brake fluid collected during system bleeding.

• | Always store brake fluid in a closed container.

• | Reseal brake fluid containers immediately after use.

• | Do not use brake fluid left in an open container or an improperly sealed container because it absorbs moisture or can become contaminated.

• | The following fluids may cause the brake fluid to boil or the rubber components in the hydraulic system to deteriorate:

- | Water

- | A silicone based fluid

- | A petroleum based fluid

- | Mineral oil

• | The following conditions provide evidence that the rubber components have deteriorated:

- | Swollen primary piston cups

- | Swollen piston cups on the drum brake wheel cylinders

- | Substandard or contaminated brake diaphragm

- | Substandard or contaminated master cylinder cover diaphragm

• | If deterioration of rubber is evident, complete the following procedure:

1. | Disassemble all of the hydraulic parts.

2. | Wash all of the parts with alcohol.

3. | Dry these parts with non-lubricated compressed air before assembly in order to keep alcohol out of the system.

• | Replace all of the rubber parts in the system, including the hoses.

• | Inspect the brake linings for fluid.

| If excessive fluid is found on the brake linings, replace the brake linings.

• | If the master cylinder piston seals are satisfactory, inspect for the following conditions:

- | Leaking

- | Excessive heat

• | If these conditions are not found, flush the hydraulic brake system. Refer to Hydraulic Brake System Flushing .