ACDelco Brake Fluid DOT 3 & DOT 4

ACDelco Brake Fluid DOT 3 & DOT 4 GMW is a premium brake and hydraulic clutch fluid for systems requiring a FMVSS No. 116 DOT 4 & DOT 3, ISO 4925 Class 6. ACDelco Brake Fluid, DOT 3 & DOT 4 GMW is suitable for all applications requiring a DOT 3 or DOT 4 performance level brake fluid and meets GMW 3356. The ACDelco Brake Fluid DOT 3 & DOT 4 GMW protects internal components from corrosion under normal use and service.


  • Increased safety through minimized drop in boiling point.
  • Will not damage the rubber components and corrode the metal parts in the brake system.
  • Fully compatible and miscible with other brake fluids of similar specification.


  • If your brake pedal feels mushy or goes all the way to the floor under heavy or repeated use, it could be a sign that your brake fluid is old and needs to be changed.
  • Poor or old brake fluid could result in brake failure or delayed brake response. This is prevented by changing your brake fluid when necessary, and using the vehicle manufacturer recommended brake fluid for your vehicle.


  • It is important to completely flush or bleed your brake fluid and replace with new fluid when the fluid has become dark or contaminated to ensure the highest levels of performance. Extreme applications like driving down mountain roads, driving or towing with heavy loads, and racing increase the rate at which your brake fluid deteriorates and will create the need for it to be changed more often.
  • Always follow vehicle manufacturer’s recommendations when adding brake fluid.
  • Do not remove master cylinder cover until area is clean of foreign matter.
  • Never wash cylinders in gasoline, kerosene, or liquids containing mineral oil.
  • Lubricate all parts with ACDelco Brake and Clutch Fluid before assembly.
  • Replenish fluid in reservoir after each cylinder is bled, or in supply tank after entire bleeding operation is complete.
  • Do not agitate tank immediately before or during bleeding operation when using pressure bleeding device.


Q: Can I change my own brake fluid?
A: No, ACDelco recommends that only trained professionals change brake fluid. Correctly flushing, filling and bleeding the system is critical to braking performance.

Q: Should I periodically change or add more brake fluid to my brake system?
A: Yes, add new fluid whenever the fluid reservoir shows fluid is needed. Additionally, change your brake fluid if the reservoir fluid is dark, murky or has significant contamination.

Q: Can I use DOT 3 brake fluid interchangeably with DOT 4 if my vehicle’s manufacturer recommends a DOT 4 brake fluid but says DOT 3 can be added if necessary?
A: No, DOT 3 can be added to a DOT 4 system but only if it is absolutely necessary, for example the fluid level is critically low. After getting to a safe area it will be necessary to flush out the system and add the correct amount of new DOT 4 fluid.

Q: Should I flush or bleed my current brake fluid before adding more?
A: No, adding fluid is a normal practice as the brakes wear. However, when changing the brake fluid the system must always be flushed first, this is the only way the system can be cleaned of contaminants. After refilling with clean fluid the system must be properly bled, otherwise the fluid level will be too low and the system may not work as needed.

Q: Can I use ACDelco Brake and Clutch Fluid, DOT 4 GMW in my vehicle that requires DOT 3?
A: Yes, DOT 4 has a higher boiling point than DOT 3 and can be used instead of DOT 3.

Q: Can I mix colors of brake fluid within my brake system?
A: Yes, the color of the new brake fluid is not critical as long as the brake fluid specification matches what is recommended for your vehicle. Only the brake fluid specification is critical.

Q: Can I use DOT 5 brake fluid with DOT 3 or DOT 4?
A: No, DOT 5 cannot be mixed with DOT 3 or DOT 4 brake fluid.

Q: Is a leak the only possible cause of reduced fluid levels in my brake system?
A: No, while the fluid level can go down due to leaks, most often the fluid level will go down as the brake pads and rotors/drums wear and the calipers must push farther to make the system work.