So the Crown Vic drives great! Comfy family mobile but it's showing sign of torque converter shudder. Very light throttle only, feels like rumble strips. The guys on crownvic.net say to do a cooler line flush plus drain the TC. Others say don't bother and just do a drain and refill. Maintenance history is unknown and judging by the cooling system it was nonexistent. The fluid is slightly brown but stills smells like ATF a little. 129k miles I'm leaning towards not flushing the system fully. Any advice guys? Thanks!