[Astroboy]

OEM hitch is bolt-on, similar to the photo.

You must forgive me for my touchpad finger-painting ...

Blue represents Hummer's ladder frame.
Red represents additional square tubings and gusset plates that are fabbed and welded by my local hitch shop (Hitch Master Inc. in Van Nuys, CA, a couple of nice guys w/ welders).

When I bought my H2, I made sure not to pick stock air suspension. I felt that it's too-complicated system that I didn't want to look after. Instead, I opted to install aftermarket supplemental airbags designed to be inserted within the coils. I just bicycle-pump them as needed, when I tow.

I think H2 makes a nice tow vehicle — more than the likes of Tahoe or Expedition because of its short overhangs that mitigates the leverage force of "trailer sway".

My impression was... H2 has somewhat-soft rear suspension which needed to be stiffened. Other factors in H2 (engine, trans, axles) are good to go, because they all come from 3/4ton parts bin...