YES, that site is very useful. Here is the main link.
It covers just about every GM vehicle in the light to medium duty range.
I have used that site many times for determining axle loads. There is a "weight calculator" where you can add up all the options one has and it will give you an actual axle weight, what is left on the axle capacity and where in relation to GVWR and GAWR you are.
It comes in handy when sizing up a TV or figuring out how TT tongue weights affect the TV.
They use to have like 4 years worth for vehicles but now I see it is down to 3 years. They roll to the next as the next model year comes out.
That site and RPO codes are unique to GM. Now that I gave up my Bowtie for towing and now have a Blue Oval I have to use different tools to accomplish the same thing. Ford has what they call a “Source Book” with a ton of useful info about the specs and weights of there trucks. However to get one, you have to go to a dealer and be interested in buying a truck. I now have a 2005 one an a 2008 F series one. Those books are online, but not open to public viewing. Or at least that I can find the link to them.
I’m sure Dodge has something too, just never been there looking yet. Point is, there is now a ton of TV info on the web, key is to have a clue what you are hunting for. The online forums help greatly in letting the average person find this stuff…. Most times all you need if a few clues on where to go digging.
Current Sunlines: 2004 T310SR, 2004 T1950, 2004 T2475, 2007 T2499, 2004 T317SR
Prior Sunlines: 2004 T2499 - Fern Blue
2005 Ford F350 Lariat, 6.8L V10 W/ 4.10 rear axle, CC, Short Bed, SRW. Reese HP trunnion bar hitch W/ HP DC
Google Custom Search For Sunline Owners Club