The lightest SuperDuty has a gas engine. Diesel SuperDuty fuel economy is a bit better, but the vehicle also weighs more and is likely to be carrying/pulling more. But regardless of whether the multiple is 2 or 3.4 or somewhere in between, it is a small fraction of the added road wear.

By the fourth power law, an unloaded diesel Superduty creates ~22x the road wear of a honda civic. Loaded can be 100x more.