[redmodelt]

I would say dry or lubed threads come into play. If the threads are lubed, it will take longer to reach the 30-35 foot pound reading, which could result in pulled thread. Charts show 2 readings for each type bolt/nut, dry or lubed. You might try a beam type torque wrench and see if that helps. At this point, would look at the thread on both the nut and bolt to see if they are pulled. Often in the past they may have been over tightened so now you are working with compromised thread, which is not allowing the correct torque.