375H&H

Had a grill guard installed this spring. Had another Cummins owner in a parking lot wonder out loud if the inside lip on the guard made my truck run hotter. Never noticed it before but the lip does block about 10% of the direct air flow to the radiator. This lip stands about 7 inches from the radiator. Now I can't stop thinking about it. Should I have that lip cut out?

96WhiteBuffalo

I do not know what year truck you have or where or how you drive it, but in the winter I have to block my radiator almost completely off to get the truck to run hot enough to work the heater.

Unless you see the thing overheating, I would not worry about 10%. These cooling systems are so overdesigned it is not funny.

375H&H

Sorry 96WhiteBuffalo, I drive a 99 Dodge 5.9L 24-valve Cummins. Newly rebuilt Automatic, 4x4 longbox extended cab.

Ran it to Reno from Montana this summer with almost no load except passengers. It ran 185 degrees most of the time and on significant grade ran up to 205. I don't know what is standard. Early this spring, I worried about it so had the radiator worked over and cleaned off. Didn't seem to make much difference. With my camper on, It will run to 210 or a little more on a significant grade but drop back to 185 on level road. By the way, on the return run to Montana, I got 19.5 mpg. Thought that was pretty good, but maybe it is standard with 155,000 miles on it.

375H&H

Just got back inside after looking at my radiator. Looks like there is a circle of oil-soaked dust and general goo blocking some of the radiator. I have contacted a guy about taking care of the problem. Thanks for the help, especially 96WhiteBuffalo. Your pics helped. Will advise. Trying to get the problem taken care of before hunting season.

DodgenIt

375H&H.. I had the same thing on my rad and it got so bad that for a few days when the heat set in here in slc, I was hittin 220* empty on normal city roads.

Pull your rad and clean it. Its way easy, There are detailed instructions in 24V engine and drivetrain titled "Engine over heating while DD" from about 3 weeks ago.

Only took me about 3 hours start to fin/cleaned up/goin in, and cost 50 bucks.
Since I cleaned mine I havent seen a degree over 190, towing, empty or up grades.

375H&H

Thanks DodgenIt. Bow season starts in Montana Saturday and things get ramped up until January 15 or so when the goose season ends. I may not have the time, but may give it a go if my contact doesn't work out.