Initially the wheel were continuing to lose air all the time. This actually started very shortly after taking delivery in Dec 2017. This continues to happen even to taday. (Feb 2022) They replace all the valve stems with old rubber type and then some updated versions. It seemed to stop. The right front and right outside rear still lose air, just not to the degree they once did. While working on the "air loss", the problem was that it was constantly putting air in the tires, I noticed that the wheels were starting to "flake apart". The wheel was self destructing. The dealership continued to monitored the wheels and eventually replaced both outside rear wheels. They are now again flaking apart.in the same place as they did before. If it keeps up the valve stem will "pop out". I will again discuss this with the dealer on 3 Mar...

Dealer replaced all six rims (steel rims didn't leak, no need to replace) at 7639 miles because rims leak air at the valve stem. Brought back to the same dealer at 13860 miles with right rear outer leaking. They replaced TPMS/valve stem and the leak stopped. Brought back to same dealer at 15000 miles again with right rear outer leaking (I bubble tested and verified it was leaking at valve stem) the dealer told me it was not leaking. Of course, it's still leaking today at 26,000 miles. Haven't been back to any dealer yet.

I bought the truck Dec 15, 2017. Problem begin within 30 days of purchase. After putting air in the left outside rear dual 3 times, as it was losing 10 -15 lbs in a week, I took it back to the dealer (55 miles). Dealer said it appeared to be the valve stem, so they replaced the metal stem with a rubber one. Then the right rear outside dual and the right front begain doing the same thing. I was continually airing up tires - hot weather, rainy times and cold days. I went back to the dealer about 2 -3 more times. Replaced valve stems (rubber). In the mean time the Left outside rear dual began to lose some air again. Went to dealer again, while they were inspecting the left rear, they found some "fracturing" around the valve stem hole. Dealer ordered new wheel and another trip got the wheel replaced.

Lately the left front tire has been losing large amounts of air. 15 -20 lbs a week. I continue to replace the air when the TPI lite comes on. In addition, some of the other tires continue to lose air. In addition, the dealer has found more "fracturing" on the right rear outside dual. As my patience continues to wear, I'm ready to leave for Florida pulling my 14K goose-neck trailer loaded. This is why I bought the truck there has never been a week when all the tires have remained a factory prescribed air pressure. The dealer says said the problem is in the wheels are the problem and need replaced.

Ford has not addressed the problem. The only 2 wheel/tires that have maintained any kind of consistent air pressure is the inside rear (right/left) duals. I have put many, many miles just going to the dealer. Help!!!!

Update from Oct 30, 2019: As of Oct 10 the dealer has repaired the "air loss problem" with new factory recommended metal valve stems. The right outer dual still has the severe pock mark. It doesn't seem to be getting any bigger. I told the dealer that as they replaced the left outer dual wheel with a similar pock mark, then they should replace the outer right wheel. They're are working on it. It is good that so far I haven't seen a TPI symbol on my dash....