I think 4400# axles are standard, as was 5200# on up to 2014 units (late 2014 and early 2015). You can see by looking at current website data... the 18HFS has a CCC of 4737# and a 30HDS 2445#; they have the same axles.
This keeps the "half-ton towable" Hyperlite line alive and which although technically true, they have pushed the limits of practicality for many of us with the 29HFS and 30HDS models. If you load two heavy bikes or heavy toys, this leaves very little CCC for all the other stuff, not to mention TWR that has to be too low in my opinion. Buyer beware. But, if you need more and are staying XLR and towable; there is always the Nitro line, which does not have to fit the half-ton towable mantra. Choices now are much better than when I ordered mine in 2013.
XLR Hyperlite 29HFS
Ram 2500 6.7L CTD
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