I know for a fact the ranger will pull ALOT more than its rated at, especially my 5spd.

Do I set any land speed records? no.

What's the most I've pulled?

Prolly right in the neighbor hood of 8-9k with out brakes (keep in mind I pull hay bales on a trailer with a top speed of 20mph cause other wise the trailer sways so bad) on our country roads.

Would I do it on the open hi-way?

Most definately not.

It's not how much your truck can pull, it's how much you can safely stop.