Well let the healers know that IC is one of the harder hitting fights in there. When you get hit you know it in there, nature if the fight. Its not something you guys should start pointing fingers at, its the fight and the place in general. They hit really hard in Ulduar.
Your gear is decent, two suggestions thou, hit some heroics and get the tier chest piece to replace the rep one. The other is your BS profession, please spend a bit of time mining and get those last 50 points to get those 2 gems slots, its one of the biggest profession upgrades a tank can have and that may help you.
Both tanks you linked are very close gear wise, the pally is a bit more closer to avoidance capped which may be some of the difference in the squisy feel your heals see.