hey Mr Allison man ! I have a 1994 allegro bay with 230 cummins, MD3060 6 speed Allison. i have never had any problems with the tranny an i have owned this coach for 8 yrs. On a trip from chattanooga tenn to franklin Ky this past christmas, the transmission would not shift into 6th gear about 1/2 way on the trip. All gears from 5th on down an reverse work fine. the transmission fluid is in the safe range, altho i notice a leak under it (very small) but i checked the fluid an was not low. no codes came up no lights came on ever thing just seem fine except wouldnt shift to 6 gear. Any help please ? thank you so much..