Integral vs Nonintegral ABS
The most common type of ABS brake system used by automobile manufacturers today is the nonintegral brake ABS system. This system uses a vacuum booster or external source for power assist. Integral units do not use an external boost source instead relying on an internal electric pump and accumulator to generate and store hydraulic pressure. An integral unit has is modular design containing many items in one and a non-integral is divided separating the different functions and parts.
In the older days the systems were integral meaning that an electric pump, modulator, accumulator, and master cylinder were all combined in one unit. This type of system is still around today, it all depends in the vehicle you are working on. The pitfall of some of these units is the price of replacement. They can be costly.
A nonintegral brake unit typically uses a vacuum booster for power assist. The booster as well as the master cylinder and hydraulic modulator are all separate units. This can be a plus when something is wrong only that part must be replaced. With an integral unit often the whole unit must be replaced costing much more than replacing one part on a non-integral unit. The nonintegral ABS units are known as add-on ABS units and have become the norm.
