I just bought a set of 2006 17" Aluminum rims from a fellow TDR member that I am going to put on my 1999 2500 diesel that had 16" steel rims. I noticed the center caps from the 2006 will not slide over my lug nuts on the steel rims and I was wondering if the lug nuts for the 2006 aluminum 17" rims were different then the lug nuts for the 1999 16" steel rims.