A couple of suggestions from reading this:
1. Fuel filter, get an aftermarket one that filters very well, FASS, Airdog etc.
This is on my to-do list; the common rails seem to be a lot pickier about fuel quality due to the higher rail pressure so well filtered fuel seems a good prescription to increase injector life. It's not in the budget yet as the drivetrain bits are taking precedence, but as a stop gap I have been religious about changing my fuel filter with every oil change. Yes, it only filters to a certain point, but it's relatively cheap insurance and makes me feel better. :sombrero:
2. I have an ARB bull bar on mine, it's pretty big but I also like it, it will definitely keep my truck safe during an accident and the install only took a few hours with one of my friends helping me out.
Would you mind posting a couple of pics of the ARB? I am specifically curious about how well it protects the low-hanging bits in the front. Intercooler, condenser, oil cooler, etc... If you can't do pics your thoughts would be appreciated.
3. Tires, I would suggest going with something besides the Toyo M/T as was previously suggested, they don't wear very well (read they are easily worn down), they are loud, and they are heavy! I think an aggressive A/T such as the Goodyear Duratrac A/T or the BFG KM2 would be a better choice. Or if you want a budget M/T check out treadwright retread tires:
https://www.treadwright.com/
The cheapskate in me is seriously considering treatwrights, but they largest they make in an E rated tire (as of yesterday, at least) is a 285/75R17. I would like to go with a 315/75R17 (~35") or bigger, but they don't offer anything in that range other than 37/12.5R16.5s.
I had been very interested in running re-centered HMMVW beadlocks at one time, due to the relative cost vice a regular beadlock and 37+ tires. The problem is that to get the wheel to clear the brakes requires so much backspacing that I would have to go with tons of lift, extended control arms, fiberglass/cut fenders, etc... The cost of the project would far outweigh the savings on the wheels/tires.
Anyway, I am leery of running D range re-treads on such a heavy vehicle. Thoughts?
4. Sway control, I love what I have from Hellwig, my truck is primarily a DD/Tow rig and the dirt that it sees is usually while pulling a trailer. With that said their airbags are great and easy to install and the same goes for the swaybar.
I am not too worried about this as I do not tow much; that being said, if I do end up with a slide in or Flip Pac setup eventually I will probably do airbags to help with the ride as well as leveling when in camp mode.
5. Gauges, I would seriously consider adding some gauges (boost, egt, trans temp) just so you know what is going on with the truck.
This is also on my long term to-do. I drive like an old lady most days since I have the bike to go fast on so I'm not too worried for the moment. At the least I will do a trans temp gauge sooner than later since that is likely the weakpoint in my power train.
6. 47RE, since you have that I am guessing either you have a low output or California version of truck, it's not as good as the 48RE (the 4 is the number of forward gears and the 8 is the torque holding capacity, meaning a trans rated with an 8 holds more torque then a 7). With this I would suggest a mag hytec double deep trans pan, it will hang just about even with the bottom of the transmission crossmember and holds 4 more quarts then stock IIRC.
Yep, standard output Cummins and the Mag-Hytec pan is on my list for when I do the tranny service, probably next month.
7. Suspension, the Carli stuff is very nice I would have that if my truck saw more dirt. If you get one of their kits you will not go wrong.
I am leaning more towards Thuren at the moment, but as you said I don't think any of those three make a bad product.
HTH.
-Alex