From a warrior prespective some guildmates have found the best choice for tanking ToGC below 5k.
You should get block value. So, first of all, forget about "this character has more gs than this other, he is better tanking". It's a clear NO.
As Warrior, Lavanthor and the second set of T9 are the way to go. Also, get your second trinket a health one, like the past brewfest event or the scarab. You should also get Shield Wall down to 2min CD.
Space your CDs and you will do fine.
TIP: Lavanthor lasts 40s. Shield Block lasts 10s. CD is 30s. So, a window of no SB of 20s. Then 10s more, which is 40s. Lavanthor gives you 2 Shield blocks.