Brake noise

We recently installed stainless flex hoses from fuselage fitting to brake units. At the same time new tires and tubes fitted. Within about one hour of operation there is an ittermittent loud moanng, low Frequency sound when light to moderate brakes are applied.
The brake pads were replaced as an attempt to fix the situation with no help. Calliper guide pins were cleaned and free. The plane has over 300 hours of no problems, till now.
Any ideas?

brake noise

Mine is the same. Replaced lines with stainless and the brakes groan now.
I am thinking the lines are flexing the assembly a bit, where it floated my readily with the old lines. Let's see if more experienced RVers weigh in here.

I've had brake groaning when not using the brakes. Even when pulling the plane out of the hangar. It was always on one side only, and has been on both sides of the plane (one at a time). My problem has in all cases been the pant mounting bracket rubbing on the rotor. Not sure if that helps but you can take a look. I have hard brake lines.

My 6A has groaned since birth

and all 900 hours since - always the right brake, goes away with harder braking. Has remained constant despite a change of pads a few hundred hours ago. A bit embarrassing when taxiing up to the fuel pumps, but I've decided it's of no operational consequence and resigned to live with it. Per-plans rigid aluminum coiled brake lines. Will be checking for signs of rubbing next time I pull the pants.

me too

I also tried hoses but couldn't solve the groaning issue. Finally went back to the original design aluminum tubes. I still have an occasional groan but I'm pretty sure it's when the tube puts a load on the caliper. I just bend the tube slightly so it allows the caliper to float and the problem goes away.

I wish there was a way to make those hoses work 'cause I've got some pretty ones I'd sure like to use ...