It's the same engine so should sound the same no matter what year explorer it's in, aside from like I said, slight differences in car design.
A lot of the first gens here that are running custom exhaust have at least an intake mod to go along with it, and a conical air filter
really changes how mean the Explorer sounds, inside and out.
I strongly suggest you get a KKM intake/filter kit to go along with whatever muffler/exhaust you get, since they are complimentary mods and flowing more air into
and out of the motor is a great way to maximize it's potential - if all other basic maintenance items are in good order.
Do NOT remove your catalytic converter unless you are replacing it!
It's against the law (to the tune of a $25,000 fine plus prison time) and does
nothing good for an Explorer. It worked decades ago for old muscle cars with carbureted V8 engines, but the 4.0L OHV is computer controlled - removing the converters from the system screws everything up and will reduce mileage, not to mention cause harmful, toxic, deadly exhaust gases. Those gases will get inside your vehicle if you have the windows open.
If the cats are so old and rusty they are falling apart, you can replace them, either with a OEM-style 2-cat system for ~$200, or you may just want to get a universal 2.5" 3-way catalytic converter for $50-80 and stick that in place of the factory converters.
You could probably have an exhaust shop do the cat pipe fabrication and install the new muffler as part of a custom system.
Instead of using the factory replacement pipes that reduce the 2.5" converter to 2.25" at the muffler, you could get a 2.5" in/out muffler to go with the 2.5" pipe that will come out of the converter, and that would make the system even louder.
It's hard to get loud only when on the gas or at idle, without getting drone at speed, even if it's limited to a certain RPM. Even the big Dynomax 17747 Super Turbo drones around 1600-1800RPM on the 4.0L OHV. You might get lucky and a certain exhaust design might not drone that much, but the bigger the pipes and the more the muffler flows (especially over the CFM the engine actually needs) the louder it will get.
That's another reason I suggested the Super Turbo 17747 and 17731- they match the flow requirements of the 4.0L OHV, stock and modified, without going too far over. They still might drone when in a system with a dump though, but not as much as a system with straight-through style muffler would.
The other option is a Dynomax VT muffler. They are a straight-through muffler, but they have a valve, which opens to let exhaust through, and acts as a regulator to keep drone down. They seem to work pretty decent for the price if you want the loudest exhaust note with the least drone.
