RCI Skids Clankier than a drawer of pots and pans

Ended up deciding to go with RCI for my skids on my TRD OR. First went with the engine, and then got the transmission skid when they were on sale with the free cat guards, great deal. Both the Aluminum version.

I initially installed the transmission skid with the cat guards, tightened everything down (a massive pain on the driver rear i might add), and all was good with no clanking other than for SOME reason, in reverse if you gave it any throttle, there was a big metal vibration sound, sort of like the guard vibrating on the cat. So, i took it off and it went away. Fast forward about 2 months, and i decide to put in on again, and a buddy and i do it on his lift. Well we install per the instructions, but to hopefully help with whatever rubbing/vibrating we heard the first time, on the rear of the transmission skid we installed 3 fender washers between the skid and the lower part of the crossmember. All was fine until the clanking started, and oh my god did it not ever stop.

Well, it would stop once you got above say 10 mph, but anytime under 10 it was clanking and banging away harder than a nightime gall in Vegas with a chip on her shoulder. Here is a link to the vid:



Now, it drove me insane so this weekend i took the transmission skid back off, torqued the engine skid, and all was fine. No more clanking or creaking or popping. Based on the videos i took, the back where we put the washers was not moving nor the source of the clank. Once i moved the go pro to the area in the video above, i could see a bit of flex between the 2 plates, and the noise is quite obvious.

SO all that said to ask, outside of maybe the fender washers being non approved from the manufacture, what could i do to remedy this? Everything was as tight as i felt comfortable with in terms of bolts.

 

Mine do not make any noise (mine happen to be steel, but probably irrelevant). I just tighten them down (up?) to "feels right", Maybe your catalytic converter guards are not tight enough ... there are many bolts for that?