Getting back to the residual pressure valves we showed you earlier, they are used in-line on a Jeep when the master cylinder you are using does not have a metering block. The red 10-lb valve is used for drum brakes and holds pressure on the wheel cylinder so the shoes won’t back off the drums. Without this part in your system you may have to pump the brakes once to get the shoes out to the drums. The 2-lb valve (top, PN260-3278) is used in systems with disc brakes when the master cylinder is mounted near or below the same vertical height as the calipers. This keeps fluid from flowing backwards within the system.