Snap: 3550 Knocking sound from undercarriage

CE: 3550-bogie 2 wheelflat ~~~~~ Snap: 3550 Knocking sound from undercarriage CE: 3550-bogie 2 wheelflat  3550 A4 wheel flat 30x30mm 3550 B4 wheel flat 20x30mm Dumpvalve test ok. Brake shoes ok. Brake pressure check ok. Notification for wheel profiling: 2606343    Done by: Martin/Rudy 45450