I don't think weight of the truck alone would allow for proper calculation.
My truck weight 10k and drives over dirt in my yard with no restrictions. Than I take my 7k forklift on semi-pneumatic tires and it will crack the sidewalks and sink in the dirt just fine.
This way, or the other nobody is engineering garage slabs to this degree. Old standards were 3" of concrete with steel bars every 18".
For pickup parking I would strongly advise 4" slab. Adding steel is optional, but not really critical.

 

I weighed mine in August because I was weighing in to do a truck pull. I don't have a CAT slip but I'll bet you anybodies truck against mine that the scales are within a hundred pounds.

My truck
2011 F350 6.7L it's a Crew Cab though so a bit more than the Super Cab. It weighs right at 8,400 pounds with dang near a full tank of fuel.

Ford Fan practically nailed it.

I am an engineer and I wouldn't build it to hold any less than 12,000 pounds. And there's also the fact that you may raise it on a jack, under the front, then you have about 65-70% of the entire truck weight sitting on the small footprint of a floor jack. I'm a little safe when it comes to that so I would put a beam in an area where a jack would likely be placed.

 

This isn't a slab on grade. It's a slab over open space. Big difference.

 

Thanks..this is what i was asking for.

The engineering spec states that weight rating is good for any 6" X 6" square area on the floor.

 

Had my 2013 F350 CC DRW Lariat w/fifth wheel & Gooseneck hardware weighed in at the CAT scales yesterday and it weighted exactly 8700 lbs. This was with a full tank of fuel (37.5 gals) & no driver/passenger(s). I have the Rhino liner and rubber Ford bed mat installed.