A '04 2wd 2500 Dodge/Cummins has a 9000 GVWR and a 6000 rawr. The 8800 gvwr shows to be the 5.7 Hemi.
I have the same truck in a '03 2500 9000 gvwr 6000 rawr Quad cab Cummins 3.73 gears NV5600 tranny with a 13350 lb tow rating.
My trucks rear axle weighs on average scales 2840 lbs with the hitch rails in the bed. This leaves my truck with 3160 lbs max for a in the bed payload.
I pull a 11200 lb 5th wheel rv trailer. Most of the time it leaves my trucks 6000 lb rated rear axle in the 5200-5400 lb range which is well under 6000 lb ratings.
The truck will have no problems pulling that size trailer. Now having said that for some unknown reason Dodge decided to drop the uppper aux overload spring pack on the 2wd 2500 '03 and up trucks. My trucks sags with 1500 lbs in the bed over the axle. So... you may have to go with SuperSprings.....air bags....have a leaf added to the spring pack or other aftermarket product if your truck sags like mine.
"good judgment comes from experience, and a lot of that comes from bad judgment" ............ Will Rogers
'03 2500 QC Dodge/Cummins HO 3.73 6 speed manual Jacobs Westach
'97 Park Avanue 28' 5er 11200 two slides