I have a 2018 2500HD Duramax. If the box is loaded with weight traction may be acceptable if on any thing but dry pavement. I have parked in my level driveway, with a packed snow covering and come back a few hours later to find in 2WD the truck will not even get out of the slight indentation from the tires without shifting to 4x4. On the road if there is snow / ice the truck is next to useless if not in 4x4. Around here it is rare to see a truck of any brand that is not 4 x 4, even the 1/2 ton series.
You don't mention mileage / condition or model / configuration. Unless you buy super cheap, you will take a beating on resale. At the moment asking / selling prices are crazy for any 2500 / 3500 DMax. If you buy an orphan now at high prices and things ever get back to normal, you will take a double beating on a 2WD.
Suggesst you check Facebook. There are several Duramax groups & ask your questions there. Ask about any issues with the 2005 version. The 2005 is probably the LLY @ 310hp & 605 lb-ft torque. If you are one of those who wants to tow @ 75 - 85 mph and for whom that is not enough power, factor in the cost for a "delete"
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