Ive been searching through old posts for glimmers of hope. Can someone expand on the "b2 piston" problem. Does this apply to my 79 300sd? It would be awesome if that it the problem cause it sounds like it can be done without taking the trans out. From what I could find on a search it seems like my symptoms are consistant with this problem in that it was doing fine in third gear or higher and once I slowed down to first and second gear speed I was then stuck. With the exception of I do not have reverse and most descriptions of this problem are a loss of foreward gears but not reverse the symptoms seem consistant. Could this be my problem?