Reese Dual Cam and Ram 3500

Do you still have the Armada and can measure the height difference of the hitch between that and the Ram which would let you know how much more to drop the hitch. I would level the trailer and measure ball height, then measure the hitch height on the Ram and that should allow you to figure out the shank drop.

First you need to hook trailer up and take it someplace level. Then measure the distance from the frame to the ground both front and rear. Take the difference in measurements and divide by 2 and this will give you the amount of additional drop you need to level TT.
Go to Etrailer and find the drawbar that you now have and the description will tell you the drop you now have. You are probably do not have that big a drop now as the drop is measured from the top of the shank in the hitch to the top of the hitch head at the lowest setting. It can be a little confusing but Etrailer provides reading that will make it abundantly clear. Reese offers 2 shanks with a larger drop, one of which is extreme. The middle one will probably suffice.
I just went through this with a new Ram 2500 and using this method was able to order the correct one and successfully level the TT.
The really long one is extreme and you probably will not need it.
Once you reference the shank you have now and the amount of additional drop needed you can call Etrailer and talk to technical assistance telling them what you now have and the additional drop needed and help you choose correctly.
Good luck.

Doug

With the trailer hitched to the truck, you are getting all the squat you are going to get in the truck's rear suspension. Measure the height of the ball where it is now with the too-short shank.

Unhitch the trailer and lower it to level, or slightly nose-low, wherever you were towing it with the Armada. Do simple subtraction math to get the difference. Add that difference to the current drop shank length. That is the MINIMUM amount of drop your new shank will need to accommodate.

Example, the tongue sits at 23" off the ground hitched to the Ram now. It sits at 19" when level. The difference is 4". Your current shank has a 6-1/2" drop. Add 4" to that. Your new shank needs to be at least a 10-1/2" drop. More is okay to an extent unless you go stupid like a 24" drop. Then you'll be plowing up pavement.