Rotating pintle hitch install on FJ40 (1 Viewer)

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I wanted a military style rotating hitch for my FJ40. This hitch is off of a 1954 Dodge M37 3/4 ton Weapons Carrier (basically a tactical 4x4 pickup, the HUMVEE of its day).

The hitch itself is simple. There are only six parts - two small parts are a large cotter pin (not shown) and a zerk grease fitting. These three photos show it cleaned up assembled and disasembled.
 
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The main body doesn't quite fit iinto the rear crossmember. The top and bottom needed to be shaved a bit. I made a template from .080" plastic to test fit and lay out bolt holes. The middle photo shows the crossmember already drilled out. Note that there are two crossmembers at this location, one nested inside the other.
 
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The rivets were a PITA to get out. In theory, the heads needed to be drilled out and the rivets could then be driven out with a hammer and heavy pin. Only one worked this way. The other three required more drilling because the rivet swelled BETWEEN the two nested crossmembers. The face of the crossmember is rather fugly now. I'd suggest grinding the rivet heads down flush, then welding them in place, then grinind smooth. I didn't do that but may do so later.

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These are the pieces of what got removed. Pieces of rivets and a 2-1/2" hole. We tried using cheap Harbor Freight hole saws, and burned two up before getting through the first crossmember. Bought one made by Rigid, and it siimple ate its way through the remainder of the first crossmember and then the second, and is still in perfect condition. Note the second crossmember is actually two pieces.

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Here I'm shaving the edges of the main body on my milling machine. In addition to removing the edges, the top and bottom edge where it meets the crossmember will have to be milled at a 45 degree angle because the inside edge of the crossmember is rounded, not square.
 
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Here's the hitch temporarily installed. Note that there is very little clearance between the bolts on the back of the rotating head and the crossmember. The bolts must be installed with the nut end facing out.
 
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Here's the whole hitch temporarily assembled, prior to painting. If you look closely, you'll see the beveled top edge of the main body.

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Here's the hitch installed with the dual pintle/ball hitch attached, and the crossmember cleaned up (wirebrushed to bare metal). I painted it with matte black Zero Rust spray paint. Large yellow cad plated washers were added to hide the rivet holes.

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And a pic of it slightly rotated.
 
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And a last pic of it from almost straight on.

I do not know yet how it is going to track with a ball hitch. If it wants to tilt under normal road conditions, I'll add a plate between the rotating head and the pintle/ball hitch, with an extension to provide a hole so I can lock the assembly in place to the crossmember using a welded on tube and a hitch pin.

While many military trailers have rotating lunette rings, not all do. And certainly no ball hitches. This allows me to take any trailer with a lunette or 2" ball off road.

BTW, with my 2-1/2" lift springs, 3" shackles and 33" tires, I had to do a SOA on my jeep trailer to get it to ride level. My trailer is still under construction, or I would have shown it hitched up.
 
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Nice I have had one on my 40 for some years now :beer:
 
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Anyone know where i can get one like this? I have the pintle just need the other part? Looks great

Thanks
Rob
 
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And a last pic of it from almost straight on.

I do not know yet how it is going to track with a ball hitch. If it wants to tilt under normal road conditions, I'll add a plate between the rotating head and the pintle/ball hitch, with an extension to provide a hole so I can lock the assembly in place to the crossmember using a welded on tube and a hitch pin.

While many military trailers have rotating lunette rings, not all do. And certainly no ball hitches. This allows me to take any trailer with a lunette or 2" ball off road.

BTW, with my 2-1/2" lift springs, 3" shackles and 33" tires, I had to do a SOA on my jeep trailer to get it to ride level. My trailer is still under construction, or I would have shown it hitched up.

I should have updated this long ago....

The hitch rotated too easily. I found the military specs and it should require the use of a long crowbar to rotate it. It is not supposed to articulate under normal use, even off-road. It is supposed to rotate only if the trailer runs out of articulation, and rotation is supposed to prevent damage to the towing vehicle or trailer. Basically it is highly controlled articulation once there is no more free articulation.

This may also be why you see pics of trailers using lock and roll style hitches flipped over. They do not have resistance to articulation at a point where the trailer may flip over. The military specs will help prevent rollovers.

BTW, I have reached free articulation limits and have exceeded them. The pintle and the lunette on the trailer have both been torqued over at a combined 45 degree angle. But the resistance prevented the trailer from flipping. I believe a lock and roll hitch would have allowed the trailer to flip.
 

titanpat57

Bigfoot?!...never heard of him...
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That could very well be the coolest thing I've seen in awhile...

"A" is Awesome...:beer:
 
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Do you have extra support on the backside of the bumper. On my rig the PO bent the bumper out tugging on something.

No extra support. Don't need it for jeep trailers. But, I'd be hesitant to use it as an anchor point. Hadn't thought about that. Will probably install a a hook on each frame rail.
 

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