Well i have been tanking for a while and for some reason i have been having the same problem i take too much damage even in heroics i have no clue why i have 27% dodge and 20 % parry i have no clue why i take so much damage everything but my new cloak is ench. here is my wow armory i got my bladed armor always up i think thats what is i just know it takes 5% off damage. and i got my rotation down.
IF you are taking unusually high damage and I am saying this with a big if since some healers like to say this about DK tanks in general without really having any basis for it, its not because of your spec and/or gear.
The first question is of course, are you sure you are not letting any mobs get behind you? After that, are you using a rotation with Death Strike to heal yourself frequently? Third are you using Rune Tap often or not (easy to forget since the cd is only 30 secs). There are still mobs out there which will hurt you a lot (for example spell flingers in Old Kingdom not having their Shaodw Blast interrupted) no matter how well geared you are.
Anti-Magic Shield is also your friend, particularly on cater heavy pulls. If you don't pop it for some pulls in Old Kingom and your healer isn't prepared, you're going to be getting a close up look at the floor.
Basically, make sure you're in the proper presence after spec swaps and use your abilities and cooldowns (VB, RT, AMS, IBF). I'd say a DK's special abilities and cooldowns are fairly critical to their ability to stay vertical. Moreso than several other tanking classes.
Yeah i do use my CD when im 50% or 35% and i have the skill that reduces damage and yeas i use DS frequently to heal my self and i never use magic shield ima start to use that in icc the majority i take is magic damage i have noticed that and yeah i do let them get behind me i think that could be a major problem...
Could you give us some examples of where you seem to be squishy?
Also your boot enchant needs to be changed, either get Tuskarr's Vitality (recommended) or the 22 Stamina Enchant.
Switch the red gem in your chest to a Dodge/Stam or Stam, you don't need the Expertise, since you are at 30.
Enchant your cloak with 225 armor.
I would suggest changing the Stam gem in your helm to Hit/Stam, since for the loss of 3 Stam you can gain 10 Hit Rating (your hit rating is low imo), but this also depends on your tanking weapon, since you are holding a fishing pole.
yeah i know my hit rating is low i am going to change the one in my helm to hit/stam and yes i know about my boots i have not gotten to realize i forget to change the ench and the cloak is fairly new so yeah. but the major places i am squishy is basically just the magic fights and trash. i started to not turn my back or just simple re-adjust my self so nothing is behind me. and i am using the AMS more.