I have a weight distributing trailer hitch i'm installing. To put on the trailer ball the mounting nut needs 400 ft. lbs of torque. Aside from that I can't get the ball to stop spinning when I try to crank down on the nut. Thus I can't get it any tighter as the ball spins on top. I'm thinking I need a very powerful impact wrench to get this thing started (and get 400 ft. lbs of torque) Any suggestions or am I on the right track? Also any suggestions on who would have an impact wrench that powerful? I stopped by a couple automotive shops but they didn't have anything near that?

Thanks,

M

Grab a pipe wrench and wedge it onto the ball, and have the pipe wrench spin to the bumper and hold itself. (Use a towel to keep from scratching.)
Then get yourself a big whopping wrench or long pipe for your 1/2 breaker bar, and torque it down. Use the German method... "Guud-en-tite"

We just use an impact with a socket that I purchased specifically for trailer balls. Once the impact starts doing it's thing the ball will not spin anymore.

If I didn't have access to this I would use some of the methods mentioned above.

Buck

Most good quality 1/2" impacts go to 400 ftlbs, Snapon, Mac to name a few.

Add a little loctitit too for extra insurance.

For the locktite, use the blue one, if you use the red one you will almost never be able to take it apart again.

No way. They say that they have that torque but they won't tighten a fastener anywhere near that. We install machinery- we go thru a couple hundred 3/4" wedge anchors a week. They take 120ft/lb. We draw them down with an impact - at 175 psi, the impacts will stop at 85ft/lbs. The rest is with a torque wrench.

You're taking your life in your own hands. I had a ball come off pulling a 30 Velocity after trusting a U-Haul installer to tighten the ball with an impact. Thank god for safety chains and automatic brakes. I had just gotten off the interstate and was going 25mph.

If the ball is spinning maybe the threads are dirty. Rust on the threads will make it virtually impossible to get the torque you need. Buy a new ball. It's your ass.

It's a brand new, everything, the whole setup.

Here's what I ended up doing. Put a towel over the ball so as not to scratch it, clamp with vise grips, turned nut to v. grips hit the shank so it was holding itself in place, cranked on it til i couldn't get it any tighter, then put a 4 foot long breaker bar over my 3/4 socket wrench, cranked on it til i couldn't move it even with the breaker bar, then a friend helped me and we turned it another full revolution.

It's "Guud-en-tite" now.