2005 Yukon

My 2002 Yukon Denali did SAME thing in SAME exact places! Hubby removed the old rusted brake line (rear), VERY CAREFULLY, so as not to break it off, and Auto Zone had the hard line and the “soft line” available for right about $50. Took him about 30 minutes to replace that rear, driver side issue. The front, under the radiator... same thing. Went to Auto Zone, got the replacement line, and ran it RIGHT BESIDE of the original because we were afraid to try to remove original and cause more damage. Got it replaces in about 30 minutes as well. we will be going ahead and replacing the passenger side rear, as well as the passenger side front hard and soft lines just to be on the safe side. I just thought that i had a very slow brake fluid leak somewhere, (simple, like a brake cylinder perhaps going bad,) But alas! This thing has disk brakes all around! Lol! So THAT was a NOT! Lol! I hit my brakes coming home a couple of days ago, and felt the pedal give way....AAAALLLLL the WAY to the floor, and it was SUDDEN! I was on a very highly travelled, traffic infested road in Jacksonville, FL, and had to get the Denali off of the side of the road... i did, was safe, checked brake fluid....EMPTY! Filled it back up, checked rear drivers wheel well for cast off fluid and found a TON of it. Eased the truck back to the farm, (stopping every 30 or so miles and before i would get into “town” and stop-n-go traffic again, to refill brake reservoir,) jacked her up, pulled off tire, crawled underneath, and the hard line, almost at the top of the pumpkin (or fluid distribution “T”), had blown several good sized “pin holes” in it. Apparently, the brake lines on these things aren’t made out of very good material, to last. Ive had 30 year old trucks with original lines for the brakes, and NEVER had to replace them...smh... But yeah, same issue on mine, and since already replaced (ing) on one side....might as well go ahead and replace em all...its GONNA have to happen sooner rather than later, anyway....