It's a Dura Ace Hollowtech II (I think that's right) crank in a Trek BB90. So one has limited preload ability with the little Shimano finger wrench. The Shimano TL-FC16 Hollowtech II Tensioner Crank. Oy vey.
IIRC the torque spec is really low - much lower than most torque wrenches I have. And the Shimano thing doesn't even have a socket for a wrench. So take up all play and put a very little tension on it using your patented FingerTork(R) Thumb and Forefinger combo wrench.