Quote Originally Posted by DmaxMaverick
Welcome to the Forums!
Thanks !

I've just been doing a little research, and what I found was that the 1500HD, 2500HD, and the 3500 all have the wider front track, while the 1500 and 2500 have the narrower front track:

* 2006 SILVERADO 1500 HD Short Bed Crew Cab
front track (inches): 68.6, rear track (inches): 66
http://tinyurl.com/2mvnmk

* 2006 SILVERADO 2500 HD Std Bed Crew Cab
front track (inches): 68.6, rear track (inches): 66
http://tinyurl.com/2ka6yh

* 2006 SILVERADO 3500 Long Bed Crew Cab
front track (inches): 68.6, rear track (inches): 74.7
http://tinyurl.com/3dk7nm

* 2006 SILVERADO 1500 Short Bed Crew Cab
front track (inches): 65, rear track (inches): 66
http://tinyurl.com/2wh6r4

* (No non-HD 2500s in 2006, but in earlier years):
2004 SILVERADO 2500 Short Bed Extend Cab
front track (inches): 65, rear track (inches): 66
http://tinyurl.com/32zgnq

Is it safe to assume any with the wider front track have the wider front frame as well ?