I have this assortment.
a 1/2" drive breaker bar
1/2" drive deep socket 1 1/8"
A box end 1 1/8" wrench.
The box end fits the 3/4" bolts where the threads stick out too far for even the deep socket. The socket will fit the head also.
The breaker bar (from Harbor Freight) is inexpensive ($20), long (24") and allows you to add a length of galvanized pipe to get lots of leverage.
Hint: When working on the hitch bolts, don't hesitate to turn the assembly over in the receiver. I always want to be pushing down on the breaker bar so if it slips I don't bash the tailgate or myself.
I can also step on the breaker bar to get lots of torque.
Originally Posted by tyggeln
An air powered driver is probably the way to go, since finding the necessary torque wrench is really tough. I recall the requirement was something like 300 ft-lbs.
Being a shade tree mechanic, I make the torque adjustments like this. How much do you weigh? 200lbs? Okay to achieve 300 ft/lbs, you want to apply that 200 lbs (stand on) the breaker bar 1.5' from the bolt.
Or if you're 150lbs, stand on the breaker bar 2' from the bolt. I've watched that Harbor Freight breaker bar bend about 10 degrees, and it didn't snap! That's when you want to be near the ground, just in case.
I considered an DeWalt impact wrench, but the cost/benefit just didn't justify it for the few times I adjust the hitch.