I am trying to decide on what injectors I would be able to use. I am thinking DDI's, DDII's or maybe 275's. I have read alot of posts from people towing with the 2s or 3s but I would like to know how speed/rpm effects the egt's. I tow a trailer loaded with snowmobiles approx 8000lbs only a couple of times a year but when I do its at 75mph on the interstate for about 16 hours one way. The speed / higher rpm (2500 at 75) is what I am concerned with on how it will effect the temps. If anyone has been doing anything similar to this I would like to hear about it. My other concern is how will the auto hold up with the II's and will I need some fuel system upgrade. The truck is stock except for the air filter. I will be getting gauges before anything. Thanks in advance!