I have a 2000 3500hd and some years ago the rear tank rotted out. I've been trying to find a replacement but to no avail
Any suggestions as to where to look would be appreciated.
Have the vin number with you when hunting.
Call Rockauto- tanks don’t always show up but they can look some up and let you know.
LKQ might also.
Check with auto body shops around you, as they buy tanks more often than mechanical repair shops do.