Decrease file size of drawing pdf

[BM_8212128]

I am creating a drawing of a vehicle model with components being mounted to the vehicle. So save from having the entire vehicle model in the assembly I created a skeleton to use as the base for the drawing. Once I create a pdf of the drawing, save as or export, the file size is massive at 70MB. This drawing is only four sheets with 3 views per sheet, is this a product of using the skeleton model or is there a way to make these files much smaller.

[kdirth]

There are a lot of things to consider. 

What is the size of the drawing?  If it is D size, the PDF is creating a 34" x 22" page, not just 8.5 x 11.  It is formatted to print clearly at the full sheet size.

Look at the content tab.  All of the items checked add more information to the file.