Towing Troubles
Part Two
Q: I own an '06 Dodge Ram 2500 Quad Cab that has 47,000 miles on it. I've performed some modifications to the truck, like a K&N cold-air intake, 5-inch turbo-back exhaust, CFM Plus intake elbow, and a Bully Dog programmer with a boost fooler. I tow a 21-foot toy hauler with three quads--all together the trailer probably weighs around 10,000 pounds loaded. When I go to Flagstaff, Arizona, to ride, there is a hill that is an 18-mile climb. When going up the hill, my EGTs will get as high as 1,250 degrees. Some people say it is OK, and others say it is too hot. What's the real answer?
Bill Shaw
Henderson, Nevada
If you're one of our readers...
If you're one of our readers who tows regularly, you may be interested to know that Chevy, Ford, and Dodge all offer less powerful engines in their medium-duty trucks. The lesson here is if you want your diesel to tow reliably forever, you need less horsepower, not more.
A: This is another common question we get here at the magazine. A lot of our readers tow, and while there isn't really one right answer, there are guidelines. Think of exhaust gas temperatures as sticking your hand in a hot oven. If you put your hand in just for a split second (say, to put some pizza in there) you're none the worse for wear. But if you leave it in (your hand, or the pizza) for a longer period of time, it will get burned. A similar effect occurs in diesel engines. While seeing 1,500 degrees on the pyrometer for a few seconds is usually OK, having it pegged at 1,500 for five minutes is sure to cause damage. While 1,200 degrees is often considered the limit for prolonged towing, time is also a factor in how an engine will respond to high EGTs. Engine design also comes into play, as the newer common-rail engines are built to handle higher temperatures from the factory.
Common-rail Cummins diesel engines are among the best heat handlers on the market today, so we'd say your 1,250 degrees is still on the safe side, but just barely. Anything above 1,300 should be kept to a few minutes, and anything above 1,400 should be limited to just a few seconds. Keep in mind these are also conservative maximums--we know of a few Dodge Cummins owners who have towed at 1,400 degrees for five minutes and lived to tell about it, but we'd never recommend someone actually go out and try it. Also, all of these temperature recommendations are pre-turbo--if your pyrometer sensor is mounted in the downpipe instead of the exhaust manifold, we'd try to stay below 1,000 degrees while towing.
If you're still worried about your exhaust gas temperatures, installing an aftermarket intercooler or water injection kit is a sure way to lower your towing EGTs. Expect a 100- to 200-degree drop with either one of these add-ons, which will bring your truck well below the safe towing threshold. If it were us, we'd probably just keep our eye on the gauge, and try to keep it below 1,300 degrees.