an exhaust inlet portion comprising an exhaust gas inlet for coupling to the exhaust system to receive exhaust gas from the exhaust system;

an exhaust diffusion section in gas flow communication with the exhaust gas inlet section, the gas diffusion section comprising a top portion, a bottom portion, and first and second side portions when the diffuser is in a first orientation, the exhaust diffusion section lacking a plurality of baffles extending lengthwise along a substantial length of the diffusion section and extending from the top portion to the bottom portion, the first and second side portions at least in part comprising diverging side walls moving in a downstream direction away from the exhaust gas inlet so as to define a gas flow passageway that increases in cross-sectional dimension along at least a portion of the exhaust diffusion section in the downstream direction;

an exhaust deflector coupled to the exhaust diffusion section and positioned to direct the flow of exhaust gas traveling through the exhaust diffusion section in downward and laterally outward directions when the diffuser is in the first orientation, the exhaust deflector being sized to direct the flow of substantially all of the exhaust gas flowing through the exhaust diffusion section in downward and laterally outward directions when the diffuser is in the first orientation, the exhaust deflector comprising a deflector proximal end portion coupled to an upper portion of the exhaust diffusion section when the diffuser is in the first orientation and a deflector distal edge and first and second deflector side edges at respective sides of the deflector, the diffuser comprising a longitudinal axis with the exhaust deflector comprising a gas deflecting surface that is angled at an obtuse angle relative to a horizontal plane parallel to the longitudinal axis of the exhaust diffuser section, the exhaust diffuser section comprising a diffuser section lower edge at the downstream end of the bottom portion of the exhaust diffuser section, a first diffuser section side edge extending upwardly from the diffuser section lower edge at the downstream end of the first side portion and a second diffuser section side edge extending upwardly from the diffuser section lower edge at the downstream end of the second side portion when the diffuser is in the first orientation, a first lateral exhaust gas flow opening being provided between the first deflector side edge and the first diffuser section side edge, a second lateral exhaust gas flow opening being provided between the second deflector side edge and the second diffuser section side edge, and a lower gas flow opening being provided between the deflector distal edge and the diffuser section lower edge.