Thank you. Just for kicks I replaced the master and still have the problem. I will certainly go after the clamp process. Good Call I'll get back to you. Thank you.
--Dan

Rear adjustment good and rear drums are new premium. The guest of course said no one was there before. I will check the push rod and check that prop valve bleeder. Fortunately I prepared the guest for this before I started the service. Thank you both for you posts.
--Dan

Hi folks,

I have a 1998 toyota 4runner 4x4 low brake peddle master not leaking and no air. Has ABS and master is not bypassing just low. 237k Has anyone come accross this before?
Thank you,
Dan

Sorry, I'm a lot more professional than that. I also need to use this forum. This was Duhhhh moment. 2001 gmc Yukon 5.3.
Thank you all so much for your help.

I have a GMC Yukon that howls/whines at start up. After a few minutes it stops. The noise is coming from a valve at the right side under the hood on top close to the fire wall. Can anyone help me with the name of this valve.