NHTSA Complaint #11612602 — 2003 FORD E-450

I have issues with brakes calipers that pistons are made of Phenolic material, replaced calipers multiple times and will fail in as little as one trip and when using RV in hot weather or too much braking like in the city even if is cold the brakes are constantly locking up to the point where the wheels won't turn, and burn I have to pull over when this happens and wait and hour or two while the brakes are smoking on the side of the road and my wife with a fire extinguisher afraid that the RV was going to burn then I reach inside with a tool to break them loose. I do not have more options for the repair as the calipers pistons are the problem every time and it became very dangerous to drive around anymore, I don't often complain of things but this is a safety issue that affected many of this vehicle owners with this type of caliper pistons. At this time the brakes are not the problem is the calipers pistons that fail no matter how old they are, as they heat up they warp or deform causing them to stick inside the hub of the caliper, I need assistance to correct this issue since ford has not provided a fix for that, I did not want to reach this point of filling a complain because is not me but if they made a bad part for the vehicle it need to be updated. I will buy the parts if there is a replacement available that wont stick inside calipers when is hot. Please note that the brakes calipers have been replace all of them then failed the same way within the first or second drive if driving down hills or traffic areas, is been confirmed that the issue is unrelated to other brake components. Thank you for your assistance.