My primary drive nut came loose today and I got the rumble strip vibe. My shifting got noticably more difficult yesterday on a long ride and so I was going to check it tonight. Well this morning on commute it went south. So don't waver, don't hesitate, check that torque or at your peril...Luckily I don't think I sheered my woodruff key as Chadley had :huh. I called my dealers Mechanic and he called Husky; evidently everyone is just fixing their own as Husky hasn't heard of the issue??? Oh well you've been warned . Oh the mechanic said he couldn't technically recommend Locktite on that nut but said a drop would help...what say ye oh wise ones? Dan Edit: read last posts, the key was definately sheared and the torque must be checked on all 610's. The blue arrow points to the culprit.