Please Help with fixing these tie down points on toy hauler

Here is a photo of the bottom of my toy hauler camper. These 2 bolts are going through the cross member of frame. They hold the D ring tie downs that are in the floor inside the toy hauler. Factory didn't even put washers or nuts on them....Duh really?

Anyway before I bolt my Beast rack down to it I gotta beef these bolts up and stop them from coming loose.

I was thinking a strip of steel with 2 holes drilled in it then washers,lock washers and nuts

Please post your suggestions on how to make it stronger. Not tons of room to work in that space because of water tank,but I can still get to it. Thanks for any info

 

Fender washers and lock nuts? That's how my tie downs are on my trailer.

 

x2 on the fender washers and lock nuts. They're already going through steel. Don't need to add a steel bar from one to the other. That would only be needed if you're trying to keep em from pulling through wood.

 

Big fender washers and regular nuts, if you want to you can tack the washers to the frame and tack the nuts to the washer, remove the bolts after welding, apply red loctite and then reinstall bolts and torque.

 

ok I will pick up the stuff tomorrow...The fender washers might overlap each other though when I use big ones. Thats why I was gonna use the steel bar then smaller washers and nuts under the bar

 

I had a couple that were too close to an edge, so I just cut them down on that one side. You could so the same by cutting both so the cut edges are together. You could just get a piece of steel and put a couple holes in it. Or just use regular washers and lock nuts. With the bolts already going through a crossmember, you shouldn't have any issue with the nuts/bolts getting pulled through, but fender washer/backing plate will help prevent the torquing effect from tightening straps a bit much.

 

I doubled up on the fender washers and went with lock washer and nut. No room to get in there and use lock nuts.
I went with new bolts. Stainless steel 1/4" x 20 x 5" long
My buddy said I should use hardened steel bolts,but couldn't find any with the threads all the up the bolt

 

Photo of my Beast Rack before it shipped