Hi,
I have a 1992 XJS V12 5.3 with lattice alloy wheels. I bought a set of replacement wheel nuts that are solid, rather than have the annoying chrome cap on them. The odd thing is that they are the correct thread, but won't fit the wheels. Basically, the nut is too wide to fit into the recess in the wheel across this:


They do fit my XK8 which, as far as I can see, uses the same wheel nut, part number CCC7028. The wheels are genuine Jaguar lattice alloys, so I'm really confused about why my original wheel nuts are a different size?