1998 GMC Suburban Owner's Manual - Page 325

Checking Brake Fluid What to Add When you do need brake fluid, use only DOT-3 brake fluid -- such as Delco Supreme 11 (GM Part No. 12377967). Use new brake fluid from a sealed container only. @ Always clean the brake fluid reservoir cap and the are around the cap before removing it. This will help keep dirt from entering the reservoir. CAUTION: With the wrong kind of fluid in your brake system, your brakes may not work well, or they may not even work at all. This could cause a crash. Always use the properbrake fluid. You can check the brake fluid without taking cap. off the Just look at the brake fluid reservoir. The fluid level should be above MIN. it isn't, have your brake system If checked to see there is a leak. if After work is done on the brake hydraulic system, make sure the level is above MIN but not over the the MAX mark or the top the window on the sideof of the reservoir. 6-33