What year is your 8.1L Suburban?
If GMT800 (2000-2006), then the receiver should be replaced with a proper one. The
OEM receiver bends and consume WD forces. So it DOES NOT transfer as much weight
to the front axle as a traditional receiver would with the same WD spring forces
If GMT900 (2007 on), then note that the receiver is welded on and is part of
the bumper crumple zone. Why it is rated or limited to a max of 1,000 in WD mode
But you said 8.1L and IIRC, there is no big block offered on the GMT900 platform