Hello, I'm seeking advice on a DR Power Equipment RWD Mower w/Briggs & Stratton Engine. I recently purchased this at a yard sale. It is a nice mower with cast aluminum deck. I've got it running nice. My question is the RWD does not feel right. Upon further examination, I just do not understand it. The belt is rotation when the engine is on and the rear wheels are not moving. When I engage the rear drive lever, the wheels engage but absolutely nothing changes with the belt or the mechanism. I'm trying to attach a video hoping for some advice. Shouldn't that transmission pivot? With the way the brackets attach the transmission, it can't pivot. The only thing part that moves is the arm the spring is attached to that does nothing. Thanks in advance. I'm trying attach a video but it is not working.