So atm im lvl 70, and i have hard times tanking because i take tons of dmg.
i just have the normal BoA gears, should i enchant something? im tired that we die a few times each dungeon bcuz i take tons of dmg.
Unless you're wearing the same greens you picked up 20 levels ago you shouldn't be taking tons of damage unless, as Demsi said above, you're not using your active mitigation properly or you're pulling too much.
One common mistake I've seen is people (at that level) is using holy power to self heal rather than to put up shield of the righteous. Don't do this. Healing is the healers job, your job is mitigation. Only use WoG if you have a good number of bastion of glory stacks, and even then, only if you need to.
Remember, tank cooldowns need to be used before you get into trouble. Don't wait until you're almost dead to pop them (guardian of ancient kings) if you pulled a ton of mobs or know the boss is about to slap you really hard then pop that cooldown.