While Jmeajh's comment is correct, I don't think that's what he's asking....
If a Ranger and a Warrior both have 6000 AC, does that mean they can tank equally, as far as AC goes?
The short answer is no. If you do some Bing/Google searches, I'm sure you'll be able to find the details, but the basics are like this: AC has internally coded caps that differ by class and armor type. So even though it says 6000 AC, you're not really getting 6000 AC. Basically you get 1 for 1 AC for the first few hundred points of AC, and how few depends on armor type. Silkies may get 200, leather 300, chain 400, and plate 500. Those numbers aren't right, but are in the ballpark, and illustrate the point. For all AC over that amount, you only get a small percentage of it in actual AC, and the percentage is best for plate, then less so for chain, less than that for leather, and worst for silk. The only exception is shield AC, which is always 1 for 1 AC, regardless of these caps and percentages.
So for 4 chars all with 6000 AC, the plate wearer will have the highest actual effective AC, then the chain wearer, then leather, then silk.
Tat
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