How much weight can a Chevy c30 truck carry?

Rear Springs on a 73-87 C30 can be rated for 8,000 lbs, 10,000 lbs, 14,000 lbs, or 16,000 lbs. However, a C30 is a 1 Ton truck, so the rule of thumb is that a C30 can carry a 2,000 lbs load in the bed of the truck ("Manufacturer's Recommendation"). This means 2,000 lbs in addition to the curb weight of the truck.

Also, you need to check your local state laws on GVWR for your specific plates. The GVWR is the combined weight of your truck plus your load. For example, my C30 weighs in at about 5,800 lbs. (I think) My license plates are only good for up to 8,000 lbs. GVWR, so the max load I can carry legally is 2,200 lbs. in the bed of the truck before I risk a MAJOR fine for being over weight.

Realistically speaking, I have had 4,500 lbs. in my single rear wheel newer SRW 3500 series. It finally set down on the overload springs at 4,000 lbs. But I was only going 4 miles up the road from the gravel pit.

I wouldn't haul more than 2,500 lbs. in a C30 for any long distance on the road for fear of tearing up the truck (without taking into consideration the legal GVWR of my license plates). Cut that number in half if you are hauling strictly offroad. Take another 500 lbs off that capacity if you are talking about the 4x4, which would be a K30 Series (added weigh to 4x4 components).