Regarding Disc Brakes - Volvo 9700 US/CAN Driver's Handbook Manual

If Something Happens 107

Regarding Disc Brakes

The brake cylinder is fitted with a release
screw, which does not protrude from the
cylinder during manual release. When
starting to release the parking brake, a red peg
emerges from the centre of the nut. It is fully
out after three turns. Full compression of the
parking brake spring requires approximately
45 turns. Whenever possible try always to
fill the parking brake cylinders with air. It
makes it easier to turn the nuts of the release
mechanisms.
T5014635