I searched around this forum to find out how to tell if an LR4 has an HD Package or not. Somebody mentioned Topix in a thread or two, but not much else, and the comment seemed to go ignored. I tried it and it works. For anyone who stumbles on this thread via a search, here is what I have found to work. Please keep in mind that I was checking 2010 - 2013 LR4's. Not sure if this shows different for 2014 and beyond. Maybe somebody shopping those model years can add to the thread. 1 - Register for Topix at http://www.landrovertechinfo.com and finalize the process with the confirmation email. 2 - Get the VIN of the Vehicle you are looking at, login to Topix 3 - Enter the VIN on the left. There are little boxes to type into, but you can paste a VIN number and it will fill it out just fine. 4 - In the "Vehicle Features" box, click the little set of horizontal lines next to the printer icon. 5 - A window will pop up. An LR4 with a Locking Diff will show: LOCKING REAR AXLE - E DIFF An open diff will show: OPEN STYLE REAR AXLE-STD DIFF Enjoy!