So basically tanking sets you want to work towards are:
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Idle set - this should be identical to your DD gear since that's the best tool a War has to hold hate with. Haste, Acc, Att, etc.
Utsutsemi Ichi & Ni set - #1 haste, haste, and haste unless you're getting haste (spell) and marches you gear won't bring you to the 50% cap on recast so gear as much haste as you can. Secondly fast cast, if you have done ACP you can get the Pld/War/Sam/Etc. body with +5 enmity and +5 fast cast. The other piece you can get is the Loquacious Earring which has approx 2% now ichi is only a 4 sec. cast timer but it does help a bit.
Enmity set - I think this is self explanatory but you'd macro this in for provoke and warcry, then take it off right away. Mostly your AF and a few cheap AH pieces should put you at well around +20 enmity.
Lastly are the 2 most optional sets. Firstly the more important -Physical Damage taken and -Magic Damage taken. The only time you use these is when you know you're going to eat a big nasty hit or say hundred fists from a Mnk. There are a few pieces that are -damage taken but most are very rare Defending Ring -10%, Valhalla Breastplate -5%, and Valhalla Helm -5% if you can get those pieces of gear your life just got incredibly easy.
Physical Damage set - Focus first on -Physical Damage which are Earth Staff and the Darksteel Harness +1 set. After that just load Def/Vit it doesn't do a whole lot but it does help.
Magical Defense set - This is a bit easier. If you're going to be tanking you should insist that you be in a party with a Whm that has Shellra, merited fully it gives -24% Magical Damage taken. Now you focus on -Magical Damage gear Iron Ram Lance, Coral/Merman's gear, and Resentment Cape. Once you hit -50% total from Shellra and gear then you focus on Magic Defense Bonus Iron Ram Haubert Set, Lamia Gear, etc.
Iron Ram Lance and Earth Staff respectively are very useful for reducing damage taken but use them under your discretion because you'll lose valuable TP which is the best hate tool you have.
The final thing is food. I would recommend either Carbonara because it provides HP and Att. HP not only provides the obvious bonuses of giving healers more time to react and avoiding being one shotted but also the higher your max HP is the less enmity you lose from taking damage. The second fairly more expensive option is Rabbit Pie this provides a huge boost to att and def.
None of gear is bad to have on hand with War if you don't mind carrying it around. I've tanked almost everything in the game pre-WoTG/ZNM (and some of that stuff anyways.) War is an excellent back up tank but even not acting as a tank having -phys/magic damage sets can save your ass as DD. There's no disadvantage to having this gear ready, apart from inventory issues. So if you have the room and extra gil it's not a bad investment and if you ever level Pld most of the gear is pretty much considered necessary. Edited, Aug 15th 2009 9:23am by OrsonBastokChampion