You're lucky. In California my pickup needs commercial plates because it has a bed. Instant double registration fee every year. The Durango on the other hand, which for that year shared many many parts including everything ahead of the firewall, isn't a commercial vehicle.
For the 5500LB weight limit, virtually all full size pickups will be over that.
Nissan Titan:
2WD regular cab 5000LBs, 4WD crew cab: 5800
Toyota Tundra:
2WD regular cab: 4600LB, 4WD crew cab: 5700
Dodge Ram 1500:
2WD regular cab: 4500LBs, 4WD crew cab: 5600
Dodge Ram 2500: (hemi)
2WD regular cab: 5300LBs, 4WD mega cab: 6300
Dodge Ram 3500: (cummins)
2WD RC SRW: 6600LBs, 4WD mega cab DRW: 7600
I'm sure Ford and Chevy are similar to Dodge's figures.