buzzing/humming noise on cold start

[lightmup]

I was not able to plug in the other night because I was at work and temps hit -7 degrees. When I started the truck in the morning aftrer cycling the manifold heaters twice there was a buzzing/humming type sound after start up that lasted until I got home (approx. 8 miles later). Has anyone else experienced this noise, it is very strange. The buzzing/humming seemed to have something to do with the brakes. When I stepped on the brake pedal I could feel the vibration through the pedal. This has occurred only one other time when it was extremely cold.

Is this normal?? If so what is this buzzing sound??

 

[DaveN]

Power steering pump - I'm not sure why, but for some reason the PS pump does that when the fluid is cold. You can do a search for more info, but most guys say that going to synthetic cures the problem.



ALSO, check your fluid level. I had a small leak, and my fluid level was low and had the same problem... . this was at 19K miles...

 

[LSMITH]

Change the fluid to a synthetic, the noise will be a lot lower. Do a search on it, has come up several times in the last few months.