Oil consumption on 6.2 diesels?

[rs74]

I have only had two 6.2's and one (85 K30) I only drove a few times. When I had my 84 short bed the first time around it used quite a bit more oil than I would think it should use. It runs like a top but does smoke quite a bit. The smoke seems to go away more after it is good and warmed up but still uses oil. Exactly what should I expect of the 6.2's as far as oil consumption within a 3000 mile period?