To perform this service, our technician will remove one of the transmission cooler lines from the transmission cooler(usually in the radiator), from that point he will attach our fluid recovery machine. The fluid is then extracted from the entire transmission, including the fluid in the converter. The new fluid is added as the old fluid is recovered. This procedure is relatively new, the old way was to remove the transmission pan, change the filter(if equipped), and fill with new fluid, but that only changed approx. one quarter of the fluid actually contained in the transmission. You wouldn’t let someone change one quarter of your engine oil would you? The recommended service intervals are: 24,000 miles-city or towing and 36,000 miles-highway.