Yes, thread sealant it will be for sure.

Threadlock only on the 3100 and 3400 engines.

Bjorn - From what I understand the 3100 and 3400 lower intakes are slightly different than the 3800 in respect to the lower manifold bolts. The 3100 and 3400 are dead holes, do not have the oil/coolant passages behind them... Correct me if I am wrong.