Not really. If the down line air pressure is higher that the brake line pressure, the check valve will prevent flow. If the brake pressure is higher, it will just add a bit more pressure to the down line. Could be a problem if you put the brakes on in flight. Your gear would come out. Don't know why you would do that? I put the brakes on the right hand slider on my 10X. Oh well, I am doing it on this jet, and we will see how it goes. I would hate to skin up that nice belly paint if I blew an airline. The prior thread about leaky fittings made me start thinking. Bob