Hey guys, long time reader first time poster ! I have an early 90’s Mack dm690s rolloff truck with the t2070 . Transmission and clutch were rebuilt and no problems since . The truck sat for about 2 months and now when I put the truck in gear and let the clutch out it won’t move at all , doesn’t even pull the engine down . The range selector will go from high to low but I just get an air sound , not the clunking noise like I am used to . I installed a new range selector on the top back drivers side of the transmission and that didn’t solve anything . Any ideas what the culprit could be ? Thanks !