It's my understanding the vans have a Turbo one step bigger than the pickups and the pickups come with an intercooler from the factory so I'm not sure if that is the issue.
Van turbo has a larger turbine hissing but a much smaller compressor housing. I swapped to a truck turbo on mine.
__________________ '99 ford e350 - 7.3L 4x4 '10 ford f150 raptor scab '53 buick special eight - the sled