[harshjay]

Hi,

I live in Calgary Canada, and we have had a pretty long and cold winter this year. I plug my 05 6.0 in all the time but during the first few seconds to perhaps a minute, the engine generates a loud whirring noise. As it heats up it goes away. Any ideas?

 

[Greeser]

I live in southwestern ontario and I know that sometimes when its real cold here or overnight that the fluid for the power steering thickens up a bit, causing the pump and the hydraboost to, in a way starve for lube, and the noise you hear is the power steering pump.

 

[nitrogen]

I'm pretty sure greeser has your answer, its not a real big deal, not really hurting anything. but if the p/s oil is getting old it might not hurt to give it a flush either.

 

[sarnott140]

mine just knocks like an SOB.

 

[kench]

I think it is the Exahust Back Pressure Valve. It helps the engine heat up in cold climates, and when normal operating temp is reached, it goes away. I really notice it from the tail pipe. Sounds like a jet taking off.