From looking at it briefly today it looks like the brakes are run off the main hydraulic system,is no master cylinder,the brake pedal is a mico hydraulic valve and goes into an accummulator then looks like it goes into the transmission but cant confirm that,i DO know there are NO brake drums or lines on the backside of ALL 4 wheels is what makes me think the brake is a clutch friction plate wet system internal to the tranny but would like a manual section for the brakes on this truck to confirm