For the heavy duty beds, in 2019, they changed the passenger side tailgate receiver hinge point from male to female. The area inside the tail lights openings were made bigger, and the passenger side has a nub below the tail light opening for a strut.I'm trying to figure out what year the changes to the beds were made for both the 2500s and 1500s. Anyone know the year or have any info on the actual differences?
Thanks for the detailed response. Now I need to go research the difference between the classic 1500 and DT 1500.2010 to present HD are the same dimensions.
2009 to present 1500/classic with 6'4 or 8 foot bed are the same dimensions as the HD.
2019 and Newer 1500 DT/new body style...the beds are different dimensions and would not work with the HD.
There is also a change at the 3rd brake light...but for most toppers it is a mute issue.
As mentioned...the tailgate/taillight area is the only thing different on the HD.
Classic 1500 is 2019 to present still using the 4th Gen cab and Bed. (2009 to current are the same.)Thanks for the detailed response. Now I need to go research the difference between the classic 1500 and DT 1500.


Thanks, very helpful!Classic 1500 is 2019 to present still using the 4th Gen cab and Bed. (2009 to current are the same.)
The easiest way to tell is a classic will have 5 lug nuts and a DT will have 6 lug nuts.
The easiest way to tell when looking at a bed ...the line indentation across the top of the bed side.
Classic/4thGen has a sort of curved line closer to the wheel well and a DT it is more straight and closer to the top
Classic/4th Gen 5 lug
View attachment 31054
DT 6 lug
View attachment 31055
You can also see the fifth gen DT is more bulged. And the bumper indent and front bottom is different.
Note: I know these are 5'7 beds...but they came up first.