CONGRATULATIONS !!!! and know how rare a 8,600 GVWR Suburban is. A big block rarer. In mint condition like what you found is rarer than finding a needle in a haystack...
But...by going to the GMT800 receiver will have you downgrade from the GMT900 receiver
The GMT900 receiver was integrated into the bumper...so it then had to have bumper crash crumple zone duties. They notched the transition bracket to the frame so that it will crumple during a rear end crash
The GMT800 receiver is one of the worst mechanical designs I've seen. Would have fired any of my engineers for designing that thing...heck wouldn't have hired that kind of engineer in the first place...
There were also production quality issues and GM said they fixed it...I'm not going to trust that and here is one failure mode...among many modes of failure. Plus it derives much of it's strength or how it works...is to transfer or depend on those two bolts to the bumper (GM had a cross bar bolted to the bumper inside) in an attempt to turn a torsional loading into a beam loading & torsion (a very bad idea, unless they beefed up both, but am assuming cost reduction...so management wouldn't have approved beefing it up)
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Need advice from the experts, Posted: 03/06/13 12:56pmThe Curt receiver you are contemplating is what I'd get for my GMT800 K3500 Suburban some day. Mine is okay for now and has served me well over the +21 years since ordered it
The modifications for yours will need to have a 1/4" or so plate made up to transition from the Curt side plates to the 'outside' of the Suburban Frame Rail.
Yes, it will be lower, but that is what good shanks will take care with their multi-hole adjustment
Good luck !!!!
