Is the low growl I hear inside the cabin a bearing of some sort?

[Benitos]

Greetings all. I have an 84 60; 150,000, mostly stock, that I bought after discovering IH8MUD. This site is so great and has really helped me get her straightened out. I was wondering if any of you vets have ever heard a low growl from inside the cabin. It is not a steady sound, it growls in four second intervals, and the sound doesn't start until she is good and warm. Again, thanks for the killer site, you all are great!

Benitos.

 

[Wile E Coyote]

Does the sound seem to increase with speed, or a while in particular gear, or while the clutch is pressed, what work have you already done on her, or??
See where I'm going with this, give us more details to work with.

 

[2mbb]

If this only or mostly happens on the freeway, I will guess this might be your fan clutch. The radiator fan has a silicone clutch that engages the fan when a certain temperature is reached under the hood. On my truck I can hear the fan cycling on and off as I am driving. Mine is on for more the four seconds, but that will depend upon how much power you are using, how hot it is outside and the condition of your trucks cooling system. The fan clutch will also engage at lower speeds, maybe even at idle, but I don't hear mine unless I'm doing above 2500 rpm.

Sounds are hard to describe. The fan clutch sounds like a fan has been turned on. I would decribe it as a low-pitch whir/hum type of noise. This fan clutch noise is normal and hearing it tells you that the fan clutch is in fact working.

 

[REKCUT]

You need to give us a few more hints. Where does it sound like its at. Like Wile E said, is it associated with any action. Can you feel anthing in the steering or in the transmission.

 

[Benitos]

Thank you for the replies. I took the truck on a 200 mile drive today. No issues and I have to report that the sound did not change or get any worse. (or better for that matter) I'm going with the fan clutch scenario put forward by 2mbb. I'll keep an ear on it and post if anything changes. I appreciate the responses. Out.

 

[REKCUT]

Good luck with that approach. My wife also just keeps driving till something fall off.