The lugs that came with my wife's 2009 focus are total junk. I did a search on it and it was surprising to read how many other people had the same thing happening with them. At this point we're going to have to completely replace them. If I let them go any longer, it's gonna be a pita getting them to back off.
https://www.caranddriver.com/news/a...g-ford-drivers-time-and-money-lawsuit-claims/
ALL cars that have the lugs with the metal jackets/covers suffer the same fate.
My former Charger, same deal, but the driver sides always swell up first. The
heat causes them to swell. Air tools scar them... Even with the Mustang, the
driver side ones were swelled up. Then the rust keeps them swelled up.. I needed
to go up to 20mm to get them off the driver side; same with my Charger, +1mm
to get them off when I had it. I did replace all the Charger ones with nice SOLID
chrome lugs... I sold the car, they're still on, and not rusted...
The best replacements are SOLID lugs, no metal jacket/cover. I just used a set from a
2013 Viper, I got them for free, so why not... I did buy solid ones prior, but they rusted,
and looked bad...
Thing is, the good ones cost $5-$9 a lug, for the nice SOLID ones. Don't get the cheap
ass eBay $24.00 set, they will rust within 5 months. The chrome plating came off
easily. I was going to evap-o-rust them all, and paint them black, but for the work,
wasn't worth it. They were solid lugs, bad quality. I was given some other lugs that fit,
then given a complete set of '13 Viper lugs, and used those. I have a good 12-15 extra
ones too.