Engine/Transmission (1998.5 - 2002) Howl from Engine Compartment

[NWhitney]

Just got back with my new to me 01 CTD and on the way home from GA noticed a very odd sound from the engine compartment. After the engine had been at operating temp for a while ~15-20min it would sound as if a small plane had lodged itself inside the front of my truck. The sound is there when you acclerate the loudest and then goes away after you get to ~1200 and then returns at ~1800. When the truck is cold the fan still turns very hard..... will turn but with just as much resistance as when hot... does this mean the fan is bad or is the small plane housed somewere else. After an 10 hour ride from northern GA to Central OH that is kinda anoying. Sometimes the noise would be worse and sometimes it would not be as bad... I am stumped.

 

[Sticks]

I think you have it figured. The fan clutch may be out. Start cheap though.



Check your coolant level in the radiator. Low coolant levels will fool the sensor into thinking it is hotter than it is.



Check your temperature sensor(s) and connection.



Then check into your clutch.

 

[NWhitney]

Is this a normal sound to a truck of this year or is this a real problem... I don't think that it is hurting anything other than my ears right now untill it gets cold. Is this the right line of thinking or is this something I need to fix right away? Is there anywere other than DC that I can get this Fan Clutch... AutoZone says they can't get one.

 

[Sticks]

For the fan to be running for a few minutes after startup is not uncommon. It should turn off soon. For it to be running full time, then there is a problem. Before you replace the fan clutch, make sure that is the problem. Do your trouble shooting first.



As for parts, the stea... dealer is the L A S T place you want to go. I would start with your local Cummins shop, Freightliner or other big rig shop, NAPA, Checker... then the dealer if no one else can get it. There is a couple of online places to get parts, like Mopar for Less, and one other that was mentioned recently on another thread.

 

[obert]

It sounds far dletched, but put an eye (and a couple fingers) to your boost hoses, particularly the lower at the aftercooler. Ive herd some very odd descriptions of the hoses starting to work loose. The latest one said it sounded like a truck blowing its horn under the hood.