[quote=patpur] .........We also found that it fused metal caps to the valve stems. .............[quote]
Nitrogen is an inert gas and will not cause oxidization, oxygen will cause it and oxygen with salt from the winter roads will cause it even faster.
If nitrogen actually caused this fusing where is the nitrogen coming from? The valve would have to be leaking to do it.
Some shops will put green plastic caps on your valve stems, replacing your fancy ones with the Chrysler logos on them. The technician will keep them .... no thanks.