The quick and primary gear is the expansion helm (10%). Double axes and Ducal Guard.
Can also add in AF+1 legs and that pretty much puts you at PDT cap.
Level 78's Stout Servant is a -9% DT. AF+1 makes it 11%
Helm+Axes+SS+DG is definitely cap. Getting all the smaller 2-3% pieces are just stuff for outside.
Cap is 87.5% if you didn't know.
Edit:
And yes, it's because you don't have a PDT set that your pets are dying so fast. When we first hit 90, we started doing the DG quest and the Pot NM in Grauberg was raping our pets. We kited it between pets. After we had our PDT+DG, we went back and killed it with zero problems. Just remember that for DG to take affect, the pet's HP already has to be below 50%. If it's at 51%, it's going to take full damage which in some cases has "one shot" our pets whereas it would have been laughable damage otherwise.
Edit 2:
I just remembered this thread:
http://www.bluegartr.com/threads/103...-effectiveness