there was a recent article on TV about some def tire valves within the last 2 years, coming from where else, china-they have no way of tracking them, but apparently they rot early, around near the wheel-i had 2 new tires mounted last year for my trailer, and doing some maint. i found one valve starting to look dry rotted-the place where i bought them said they would take care of it, but had'nt heard of the problem-they suspect there could be millions of those things floating around, repackaged and sent out
they tell you to wiggle them around and look for cracks

 

I like metal stems for that reason. When I was racing motorcyles, that was one of the first things I changed. Trailer tires are a good place for metal.
Most trailers don't get much attention and tires don't wear out as often.

 

I had new tires put on the back of my truck about a year and a half ago. A few months ago I had to have both rear valve stems replaced. One was leaking bad and the other was very dry rotted.

 

They are from China. Bend them side to side, and if it leaks replace.

 

I got a recall notice from Discount tires where I had 4 new tires put on last summer to bring it back for a new valves. I didn't have any problems with mine,but they changed all 4 anyway.

 

I had a tire on my truck go flat on me on the interstate couple months ago due to a cracked valve stem. Ruined the tire. Plus I was on the side of the highway and realized I didn't have a lug wrench to fit my aftermarket lug nuts. That sucked.