I'll keep this short with my opinions:

6" suspension lift will easily fit 35's. If you want a 3" body lift as well, it'll make 35's look tiny. You can fit 37's with that setup. Check out RubberFrog for the 6"+3" lift

For gearing, you dont need to, but yes it would absolutely help, especially with a 35 or 37 tire. Your mpgs will improve in city and supposedly decrease on highway slightly, but i havent noticed any change on highway. You'll definitely feel the seat of the pants difference though with 4.56. BIG, BAD, LOUD, & FAST is better than big bad and loud.

As for the loud, check with your specific emissions laws. some states will automatically fail you for relocating the stock cats, which is what you'll have to do for longtubes. for the longtubes, i recommend pacesetter. (moesperformance.com or airram.com). They are a fraction of the cost, and just as good. For longevity, make sure they get the jethot ceramic coating inside and out. These hemi's dont really benefit a whole from a true dual vs. fake dual due to the design of the undercarriage and the routing of the pipes. If you choose to do true-dual you'd go header-cat-muffler, tip on each side with an h-pipe connecting the two between the cats and muffler. X-pipes dont work as well either because of the design. X-pipes need the pipes between them and the headers to be the same length --again not possible with the undercarriage design.

For the muffler, people swear by Aero3030, and magnaflow. I'd stay away from hooker, maxflow, and flowmaster.

Undercarriage coating is not necessary. Just wash it often. Keep that truck pretty for the business!

 

oh, and keep your stock cats. they are already high-flowing. aftermarket high-flow cats are a waste of mod money

 

I would agree AF, that's why I tried in an off way if he was gonna do it run a 4" lift with a 3" body lift. 7" lift will ride with 35's or just a little larger will save you a few bucks on new tires since you want to keep the truck a long time. If you want to go with 20's you can, but you're paying more money for less rubber IMO. 18's will ride a little smoother than 20's and you'll save a **** ton of money on tires over 20's.

 

plus, maybe its my old school taste, but 20's are WAY too big for a 35" tire if you want the offroad look. it really makes the tire look too small. 20's belong on 38+

 

+1 good call.

 

So with a fake dual setup, would I only have one muffler? If only one muffler, do the pipes from the muffler have to be the same length?

 

This is usually known as a catback system where it runs a SI/DO muffler. But even then the pipe coming from the muffler will no be the same length unless the both go out the same side

 

Check RubberFrog's setup as mentioned earlier. He has a 6" suspension lift along witha 3" body lift.....and it looks BAD-***! I think he is running 35" tires as well. But it looks real mean.....