Rear license plate rattling

[dave73]

On my 73 challenger, should there be a mounting bracket for the license plate that attaches to the rear valance? My plate is currently mounted direct to the valance with license plate inserts, but only the bottom has holes to mount. The top is loose and rattles, making an annoying noise while driving.

[RUNCHARGER]

Does it have a kind of triangulated bracket with a small hole on top for a rubber bumper?

[YellowThumper]

I know the later models have a bracket the plate mounts to. This was to move plates outward when the bumpers also moved outward.
This bracket has the 2 mounting points on bottom and a hole for rubber bumper on top. IIRC the panels are the same way without bracket.

[Burdar]

If your bumpers are in the 73 position, you need that triangular bracket to move the plate out farther.  Otherwise the license plate light won't illuminate the plate.  That's why the factory used that bracket. 

The quick fix for the rattle is to just put some strip calk or double sided foam tape on the plate.

[YellowThumper]

If your bumpers are in the 73 outward position. Yes, there should be a bracket to hold the plate off of tail pan. It mimics the same mounting points directly on the pan. Even with bracket the pan still retains the original hole stampings.
See pic. The 3 circles. 2 are the square mountings and the 3rd is hole for rubber bumper. Again bracket and panel has this same mounting and bumper locations.

[dave73]

My bumpers are in the 70 position. As a temporary fix over the weekend, I put some double sided tape on the top of the plate. Looking for more the "correct" fix

[RUNCHARGER]

This is what you need in the top hole in the center.

https://www.classicindustries.com/product/1970/dodge/challenger/parts/md2073.html

[YellowThumper]

Yes that is it.
And wholly crap that is a horrible part pictured. Could have cleaned some of the flash off for the sales pic.

[Burdar]

If the lower bolts don't hold the plate tight, that bumper might not do much.  It might still rattle.  I don't see double sided tape as being a bad fix.  Stuff like that is done every day by dealerships on new cars.  Hopefully the rubber bumper fixes it though.

[anlauto]

Try putting new plastic squares in, so the bottom two bolts will tighten up nice, and also install the correct rubber bumper in the center as mentioned. With everything new in place the plate should not rattle. 

[dave73]

Thanks guys

[YellowThumper]

Try putting new plastic squares in, so the bottom two bolts will tighten up nice, and also install the correct rubber bumper in the center as mentioned. With everything new in place the plate should not rattle. 

Along with this make sure the plate is not bent where the bolts hold it. If bent, flatten it out again. Similar to making sure valve covers are flat at bolt holes.
Had to do this with mine.