Engine/Transmission (1994 - 1998) Any ideas on what this is?

[kwedberg]

I have been hearing a strange sound lately while driving on the highway on the last couple of trips. Everything sounds normal, then all of a sudden it sounds like a fan noise kicks in on the motor, revs up (not the motor, the noise), then releases and goes away. All of this last approx 25 seconds. Is this something with the turbo? If so, why all of sudden is this happening on flat stretches at highway speed? I do not remember hearing this before.



thanks

 

[Bhale]

I've had a noise like that before but only when climbing a big hill with a load and the pedal to the floor. Mine is a deep throaty (sp?)sound almost like it's coming from deep inside a tube or something. Haven't heard it for about 2 years but the first time it was right after i plugged the wastegate.



It'll be interesting what the pro's think...



Brian

 

[baby.driver]

Sounds alot like the radiator fan to me. Checked your coolant level lately?

 

[Deezul1]

Watch your temp gauge and if the noise re occurs while the gauge is higher than normal its the fan clutch engaging and the temp should go back down fairly quickly.

 

[Missouri Mule]

Sounds like the fan is engaging.

 

[kwedberg]

thanks for the replies. regarding the temp gauge, I have not seen any changes in the temp reading during hearing the sound. I will check my fluid level on the radiator to see if it is low. I did not know there was an electric fan that engaged and disengaged! I will let you know

 

[GSchlegel]

kwedberg,



Your truck doesn't have an elec. cooling fan. They are talking about the engine driven fan, when the thermal clutch engages, the fan speeds up and makes a lot of noise as it moves gobs of air.



Gene

 

[kwedberg]

Thanks for the explanation Gene. I was totally unaware of the thermal cluth that could engage. You guys are great.