When the truck sits for a wile, like overnight, the breaks get mushy. After pumping all is well. During this interval of mushiness when applying the breaks the pedal can get close to the end of its travail. Sometimes it sounds and feels as if the front left (US) sensor/exciter ring are making contact. Given the information I've been able to dig up here, the mushiness may be a master cylinder issue. Using a hand held vacuum pump I bled the breaks replacing about 250ml of dot 4 with no apparent change. Your thoughts please.

TheIcySea

New to me 1998 SE Discovery, 109K, Changed the oil w/15W40, Replaced sub speakers w/DII set from a J-yard

 

Most likely have a failing master cylinder, that will be the first place to stop.
You will want to do a 2 quart bleed as part of the process.

 

Mike

Thanx for the fast reply. I think your right.
Any suggestions on ware to get the parts. What do you think about the ratcheting sound? Could it be the ball joints making a fuss? Sounds to me to be the ABS ring on the port side front, but I'm just an old sailor, so I'm guessing.

Ben
98 Disco SE. It's red, cool.

 

If the sound only happens when applying the brakes, I would pull the pads on that side and see if there's crud or something in there making contact.

The best price I could find on a new one was http://www.rovahfarm.com/DiscoIBrakes.htm