How to add hydraulic fluid to a square body Chevy dump truck. 1988 Chevy R30 dump truck. 

Maybe 2 tons. It depends on the truck. The GVWR for an 87 R30 is around 9000 - 10000lbs I think, depending on model and specs. How much does the truck weigh empty? Subtract that from the GVWR and that should be how much you can haul. If you upgrade things like suspension, tires, brakes, etc then you could probably haul more but I’d be careful if the DOT pulls you over for inspection.

My 85 F350 has a GVWR of 11,000 and weighs 6,500 pounds. That leaves me with 4,500 for payload. So, yours would likely be similar. However, I haul 6,000 pounds regularly.

I've hauled 4-5 tons in my 1988 R30 but only on my property backfilling a basement. I don't put that much in it anymore.

@@tszymk77 I haul 3 yards if topsoil regularly. Also, sometimes pull a 1,000 pound trailer with a 2,000 pound mini skid steer along with a 6,000 load in the back altogether. I bought my dump truck off an excavation contractor that was in the process of retiring. He put .533 gears in it. Sucks having to shift so much, but makes a big difference in the hills when fully loaded.