I would be asking for a total refund: there is simply no reason to be anywhere near gross weight much less over weight. Man I built my van so light I'm complaining about the harsh ride. It's a 170 4x4 and I just replaced my springs on the rear to a much more compliant set from a passenger van. I have a set of the largest AGM batteries I could afford and 40 gallons of water. I also have 3 solar panels mounted to a full length roof rack. Not to mention we have a King sized 10" memory foam mattress in the very rear of the van.We recently had our new van (2019; 170ext; 2500 4WD; 9,050 GVWR) converted, and I just had it weighed at about 9,500 (full water, full gas, full passengers, partial gear). The plan was to finish out the rest of the conversion with a roof rack, side ladder, and awning, but my calculations say the extra weight (plus some additional cargo) could put us up to about 10,200 (13% over GVWR). It does sag a bit in the back, and can be sluggish uphills, but it doesn't seem like anything that's too problematic.
The (reputable) outfitter company I'm using to do all the conversion work is telling me that it's not uncommon for 170ext's to exceed their GVWR limit, and that there shouldn't be any unusual wear & tear on brakes, engine, etc. since the drivetrain of this van is the same that is used for other models that are capable of about 12,000 GVWR. He said the main issue will be balance / sag and comfort of the ride, which can all be addressed with an after-market suspension package (Van Compass + Fox shocks).
I was originally going to hold out for the 3500XD model with the higher payload, but my outfitter assured me the 2500 would handle our build no problem.
Is he just feeding me nonsense to cover himself, or will the suspension really resolve any overweight issues? Should I avoid adding any additional weight? And should I have a bigger argument with my outfitter?
Take the van out to the interstate with cold tires and watch the air-pressure climb as you drive. Be sure they are at recommended PSI before you start. With such a heavy build I would not be surprised to see 15 PSI increase on the rear and hardly any increase in the front. You got to remove something and if it were me, I would remove everything.