Had a really cold morning today, and when I started my truck up, the alternator "growled" and carried on until the intake heater kicked off, and then it was fine once the voltage came up. Is this ok? I even had the truck plugged in over night, and the block heater is working cause the intake heater didn't stay on as long as it would have if I hadn't plugged it in. I'm just concerned cause i just replaced the alternator last summer and I don't wanna trash this one. I always make sure I have all electrical accessories turned off when I start it up in cold weather. I'm wondering if my batteries are just starting to get weak. They are the factory originals. It cranks over fine, maybe slightly slower than it used to. I'm thinking the heater just draws them down that much that the alternator has to work its butt off to compensate.

 

Power steering pump more than likely.

Drive it like you stole it.

If it bothers you replace the PS fluid with synthetic.

 

Its not the PS pump. It only does it on really cold mornings the when I first start it up and the intake heater is on. Once it kicks out that first time and my voltage starts to climb, its fine. then the heater goes thru its normal cycle routine, and all is well. I've already changed over to syn. ps fluid.

 

Arching in the commutator? Or is that in generators only? Someone help here, I haven't been inside either one for years. If your brushes are arcing to the commutator, it will make sort of a buzzing noise. Put your radio on AM. If you can hear the same buzz in the radio, that's the problem.

 

I wanted to try it that trick this evening after work, but it didn't make the noise. It only seems to do it when it gets around 25*F or colder. I think it just has to work so hard to charge the batteries after the heater kicks in the first time.

 

Alternators have "slip rings" and brushes, as for the grinding/howling, my truck did it from new when starting in very cold temps, even though I was always plugged in. I don't think it was the alternator as I'm still on the original one 7 years later and no problems. My truck doesn't get cold soaked like it used to but if I remember right the grinding/howling stopped when I switched engine oil to a full synthetic 5-40, at the same time I switched to synthetic PS fluid. The noise was soooo bad you would swear that someone was beating on it with a sledge so if you are running 15-40 try a lighter grade engine oil.