Sameheller, I'm giving you my two cents as a Tacoma owner, but keep in mind that there will be lots of different opinions.
The year of your Tacoma puts it into the "1st Gen" category. 1996-2004. Most parts are fully interchangeable between those years as the mechanics and frame of the Tacoma are the same. Some interior instrumentation changes for 2000-2004, but under the skin they are the same exact same truck. Might be some small electronics under the hood that are different, but not really a big deal. Some mechanical parts are slightly different for 2001-2004 when ordering replacement parts.
I have an extended cab, 4x4, 6 cyl, manual tranny. So mechanically I have different config versus yours, but still the same base truck. I have an Eagle on the back which I flip on/off when I'm not using the truck for other purposes. I'm assuming you are using the word "extended cab" correctly for this model. That means it's a two-door with couple of extra feet of interior space behind the drivers seat. "Extra cab" Tacoma's are the 4-door version.
The comments from Sleddog are encouraging and my prior Tacoma was a 4cyl engine which was a beast. I thrashed that truck and it kept on giving. But so slow going up hills/mountains when I maxed the payload! After owning my existing 6 cylinder for over 15 years I would never go back to a 4cyl. for carrying a camper. Gas mileage is not all that different between 4 and 6 cylinder when maxing out the payload.
I don't do heavy-duty wheeling, but do enjoy going down the forest service road less traveled, which sometimes becomes a cow path. No winch, etc. But after driving the back country, I would never leave home without 4wd. It's very easy to view a road/path from the drivers seat and think "it's not that bad". The 4wd has gotten me out of several situations quickly and easily. Otherwise I might have spent a few hours trying to extract my rig and ruining an otherwise great day. And 4wd adds significant driving confidence on gravel roads at 30-50 mph when 2wd causes some fish tailing.
My Eagle is a turn-of-the-century camper version, which means it not a stripped down shell and has a 3-way frig, stove, sink, beds, etc. The camper empty dry weight is 900 pounds (confirmed with scale at factory). When loaded with our camping gear, water, etc, it's maxing out my payload capacity. Keep in mind that axle weight is more a determinate of carrying capacity than gross vehicle weight. A camper will put most of the weight on the rear axle. The sticker on your door breaks down the front/rear weight capacity. Go to a public scale and have the truck weighed 3 times: front axle on scale, rear axle on scale, and total weight. If you want to exceed the rear weight, that's up to you. I know that I do on a regular basis and don't see any ill effects. Tacomas are tough but things do break.
I only added air bags to the rear suspension to level it out with camper. I also got adjustable Rancho shocks on all 4 corners, but I might have been able to get by without either or both. The leaf springs on the rear of our trucks are pretty good, but they are also getting old because of the vintage. I got air shocks so I could reduce ride harshness when camper was not on the truck. Also, Taco's are famous for the "Taco lean", which means the drivers side of the vehicle sits about 1-inch lower than the passenger side because the gas tank, driver and battery are all on the same side. It became worse with my camper because the water tank, propane tank, and entire kitchen galley (frig, stove, sink) are also on the driver's side. The air bags can be installed to be independent, so I inflate the driver's side airbag to take out the "Taco lean".
I don't have E-rated tires but I might switch over to them when I need new ones. I didn't want a rough ride on the freeway (but my Taco already is much stiffer than any passenger vehicle), so I got tires which are suppose to be a compromise between off-road and highway. Bridgestone Revo 2 (now called Revo 3). Going into the 3rd year with these, and they seem to be adequate for my off-road needs. I didn't want a tire with an agressive off-road pattern as they tend to be noisy on the highway. I don't really notice any noise from the Brigestones, but truck has other noise at freeway speeds from engine, wind, etc.
Some general observations/tips:
Tip #1 - Your truck has a strong following on Tacoma World (first gen forum). Use it as a resource. There are thousands of members. Also use the search feature as any questions regarding LSD and such have been asked and re-hashed on that forum many times.
Tip#2 - Your truck is approaching 20 years old. Mine is 22 years. Many people embark on a "mid-life refresh" when their truck is in the 150k-200k mileage range. Mechanical parts get old, Certain parts are known to have problems at that age. Radiator, rubber components, etc.
Tip#3 - Have Fun!
