Residual Check Valves

[LDO]

Ok, 57 3100 with the CPP complete front disk brake kit. Booster & MC are mounted in original location under cab.

I have the red 10lbs check valve on the rear drums, 2lb blue check valve on the fonts. I know the check valves are used when the MC is lower than the calipers and mine looks like the MC is slightly above them just from 'eyeballing' it.

Came back from my test drive yesterday and smelled hot brakes and they were smoking a little. It also felt as if the truck had to overcome the dragging brakes when starting from a stop.

When I pump up the brakes, my front disks lock up and stay locked up until I tap the brake pedal and then it releases pressure. Haven't checked the rear drums yet.

Is this a normal operation for these check valves?
Do I need these in the system?
Anyone run a similar setup as mine without them?

Thanks for the help!