I was looking for a good write up on this and couldnt find one so i figured i could make one and help out hopefully! This will take you step by step how to remove the loose floppy arm rest fix it and put it all back together. Took me about 2 hours to do.
First off you will need a few standard tools.
1: socket set
2: torx bit set
3: screw drivers, philips and regular
Now lets get started...first off you need to pull off the plastic covers on the side of the arm rest...put both driver and passenger seats all the way forward and tilted up. I jumped in the back to do the whole process. Now on the drivers side there is a flat plastic piece on the inside inbetween the armrest and seat part, it will pop right off. Once thats off, there are 2 philips screws where the seatbelt is for the middle seat at the bottom of the big plastic piece...take those 2 out and slide the whole piece towards the celing and then out and it should come right off. Next the passenger side has one plastic piece covering the bolts also. It has a barbed plastic fastner right in the middle, pull it strait out and it should come off...now you should be about here...
This is the passenger side. The driver side looks about the same, just with a big torx bolt to hold it in place.
Now once you have those out, simply slide the peg out of the driver side and lift it out of the truck.
Now its time to take the thing apart...you need a medium size flat screw driver to stick in between the little black ring that holds the material in place, and the inner plastic compartment. Pry outward on the black ring and it should snap out, you should hear it, just pic a spot on a long side to start, not the front or back. Once youve got some material pulled out, work your way around the back so that you've got it pulled out all the way except for where it goes under the cup holder cushion. Now slide the back rest foam out and invert the cover material so that you can get to the underside of the cup holder. Next you need to get that cushion off, you will see a bunch of white clips that look like this...
These are really tight so this part is a bit of a trick...you'll need a few flat screw drivers for this...What you need to do is pry in between the hook part and black piece and push down with your thumb at the same time...getting started is the hardest because you need to get a few of them down before they actually stay there without popping back up. Just start at one end and work your way around.
Once you get it to pop off you'll have this piece...and yes i did break one tab off...and no it doesnt affect anything in the end...
Ok now its time to fix whats actually wrong with the arm rest part...every screw in mine was out or broke...all of the ones that mount flat on the rear part of the arm rest were just loose so i put the same screws back in them. as for the front, they all have pegs that the screws go into to hold the metal piece up from the plastic. So all the postson mine were broke, so i took 2, 1/4" bolts and drilled out the metal and through the plastic where its indented on the top side and simply bolted it down with the head of the bolt on the metal side.
I only put 2 bolts in because i figured it would be strong enough with just them and didnt put anything way up front by the cup holders.
Ok now we got another difficult task...putting the material back on...so grab the back rest foam and stretck the fabric back over it and the newly modded arm rest. Next fit our black plastic hold down ring back on. Ok now you need to pick a spot to start fastening the fabric. Try getting a corner snugged up nice and push the black plastic retainer down into the channel with the fabric. Then work your way around...its a pain in the rear to get it stretched nice and tight but it is possible...I also used my flat screw driver in places to jam the fabric down in. And if there is a loose spot, just pop that part of the ring off and tighten up the fabric...and there we go...it should turn out something like this...
I did tighten up some loose spots in the fabric once it was back in the truck also...so then just put it back in...opposite of pulling it out, tighten the 3 bolts, snap the plastic covers back on and youre done...with a solid arm/back rest once again