Ok, here goes......
I have an '05 KC 4x4 SE, Big Tow/OR pkg that I bought new in March of 2005. Had 80 miles on it when I picked it up. Has 202k+ on it now, still pulls strong as when new, shifts same as when new, and has had no engine, transmission, t-case or front diff work done. Changed oil every 3k like clockwork. Not as religious with the other fluids though (1st trans flush @ 160k - almost looked like new, 1st t-case fluid @ 140k, when I also put a new Stillen aluminum radiator in it and changed the coolant for the 1st time). Front diff oil twice (just did 2nd time last week), rear diff oil every 30-40k since about 110k (original rear went @ 61k - broken spider gears, replaced under warranty with "upgraded" 4-spider rear - just now starting to get some whine due to worn bearings). Both front hubs - left @ 112k, right @ 165k, all u-joints (rears twice, getting ready to replace all again due to slight wear & 1 cap won't take grease). Recently replace r/s outer tie rod end. Radiator cap when I did radiator, battery at about the 4 yr mark. The only bulbs I've ever had to replace due to being blown were the ones at the tailgate and the puddle lamps in the door panels. Replaced 1 broken AC vent in dash when the kids broke it. Replaced driver's door window motor due to worn out brushes (if I could've gotten brushes I coulda fixed myself real cheap).
Brakes were done by dealer under warranty until 36 month mark (about 90k) due to recall policy for brake shudder - I've done front rotrs twice myself, and front pads twice myself - rears were replaced by dealer at 90k when they did last "warranty" brake job. Fixed broken tailpipe/muffler joint twice myself (rotted out, I welded adapter on & used clamp) - keep in mind also that my truck spent the majority of it's life in upstate NY. All the exhaust is original except that. I do have a cracked r/s manifold - been leaking since 75k, but I never took it in cuz I figured it was out of warranty - it has finally gotten to the point that the CEL is on now. A couple EVAP solenoids, and 4 sets of tires (OEM BF Goodrich tires don't last, switched to Toyo Open Countrys and just recently Firestones, stock size). Front calipers at about 180k due to binding pistons.
Serpentine belts every 60-75k, spark plugs every 75k, air filters as needed. Did tweak a rear shackle early on, but that was b/c I severely overloaded the truck and went thru a ditch (I bet I had 2500 lbs on it). I routinely pull 3500 lbs of MX bikes/quads on my 12' trailer, used to pull an 18' flatbed full of quads/bikes & camping/racing gear, have pulled an 18' flatbed w/Firebird on it no problems (prolly 6k or so, trailer & car). Towed a 30,000+ lb dumptruck about 200' in the snow in 4-low w/rear diff locked. Got as high as 17mpg when new, on the highway, @ 75mph cruise. Average about 14.5mpg in city w/no AC, 12.5 in snow w/4WD on, 10-11 towing thru PA w/3500-4000 lbs + full bed of gear @70-75mph.
Never left me stranded, even when rear diff went - I drove it for almost 2 weeks making noise before I took it to dealer. I don't baby the truck per se, but I certainly don't beat it into the ground either. Has been off-road, but not heavy wheeling or anything major. IMHO, one of the best trucks I've ever had - I know for a fact that a domestic truck would've had more problems - every person I know with a domestic truck has had more issues at earlier mileages than I have. The only major issue I've had is the rear end - but since replaced, no repeat failure. Plus, I may have caused that with the dump-truck pulling deal anyway (rear diff failed just weeks after that).
My complaints with the truck are mostly related to my desire for a 3/4-1-ton truck (I want a 5th wheel or large trailer, but the Titan is rated for 9400 lbs), and the fuel mileage when towing (though the diesels today aren't much better until the loads get real heavy or the hills get steep). For a 1/2-ton, it rocks. As far as the comment about getting a diesel for towing, I'll say this - I've done the math, and unless you NEED the towing capacity of a diesel due to the weight of what you are towing, it does not financially work out any better having the diesel compared to a gas UNLESS you keep the truck for over 300k, and even then, it can easily swing the other way if you need a major engine repair on the diesel (like a turbo, or injectors) as the parts are very expensive (in comparison, if you had an F350 with the 6.8 V-10, a FORD reman engine w/warranty runs under 4k. Compare to the 6.0/6.4 PowerStroke injectors @ $300 each x8, plus labor, and you still have a motor with how many miles on it? I'll take the new V-10 with ZERO miles for my money). So, it all depends on what you want. For me, I can't swing a new truck anytime soon, so the Titan stays for a while. Who knows, by the time I can, I may just keep her and do a rebuild/upgrade instead. She is paid for, after all. Who wants a $700/month payment anyway (on a $60k truck). I've no doubt that the truck is capable of more towing capacity if the frame is reinforced, brakes/axles upgraded, and suspension is upgraded. The engine and trans can handle more, and an overdrive unit and supercharger could help with both increased power/towing and improved mileage.
My advice? Look for an '07 or newer if you can (as they had the 4-pinion rear diff from the factory), one with low miles, 1 owner, and maintenance history that shows it's been well cared for. It may cost more up front, but it's money well spent IMO. Get as close to that "ideal" truck as you can, and I think you'll be more than happy. Good luck, and I hope this info helped you, and/or someone else!