I had a 2007 Ram 3500 SRW and went to a 2014 Ram 2500 with the coil springs. The 2500 squatted less with the same load, and rode way better. It also didn't have axle wrap/hop in low traction conditions. Take a look under the rear above the rear diff. There's a 3rd shock absorber up there.
I also compared squat, using my friends 2014 3500 SRW and a 14,000# 5er. The 3500 squatted about 3/4" less than my 2500. The 2500 rode level with a 14k 5er on it.
My 2014 Ram 2500 6.4L Hemi had 3000# payload. The diesels are less - in all 3 brands as any 2500 series truck is limited to a 10k GVWR.