Eh I bet it’s weight is right around 6400 tops. Buddy I used to truck pull with in the gas class had a mid 70s 460 ford 350 4x4 on 39s. His weighed less than 6500.
My 99 diesel one ton 4x4 pulling truck in full trim weighed in at 7800 pounds with full tank of fuel and me in it.
My 78 3/4 dodge with the 408 weighs just over 6000
Your 99 diesel, is that a Dodge ?
Bill