Something is squealing like a pig under the hood. I believe it is the alternator. Took the truck in for it, they say its normal for some noise. What do you guys think? Can get really annoying. I have for sure ruled out the belt. Thanks in advance.

If it's squealing then it isn't normal. You may be able to isolate it by turning pulleys by hand without having the belt on and the engine off. If that doesn't get it you could start it without the belt and if the noise is gone, then you have a reasonable idea where the noise is not coming from.

Take the belt loose and see if it goes away. That will narrow it down to accessory noise or not. Could be water pump also. Use a screwdriver as a listening device by holding it to near suspected noise origin and put your ear against it.

My guess would be bad bearings in the alternator.

A Screwdriver?????That Eric is sure high tech! I always use a piece of broom handle!

I had an idler arm pulley going bad on my GMC that also made a load squealing noise, you might want to check those out to.

I borrowed a mechanics stethoscope from a buddy of mine, and it IS the alternator. Do I just go pick up a new one and install myself, or should I take it in and have it done? I have replaced many parts on my F250 diesel, so I can't see this being too much of a challenge. Thanks for all the replies.

I borrowed a mechanics stethoscope from a buddy of mine, and it IS the alternator. Do I just go pick up a new one and install myself, or should I take it in and have it done? I have replaced many parts on my F250 diesel, so I can't see this being too much of a challenge. Thanks for all the replies.

If your still under 3yr/36,000 mile let the dealer replace it under warranty. Why pay for something you can get for free? Well, you did pay for it in the price http://www.dieselplace.com/forum/smileys/Ermm.gif

Jim

i have something similar going on w/my truck....usually first start up of the day or like 10-15 secs,,,,and then everytime i shut it off it squeaks...mentioned it to the service folk back in may when i had some stuff done and they printed off a bulletin of sorts.. #PI01242A where it stated its perfectly normal and all diesels do it, as its due to the sudden shutdown of a diesel...http://www.dieselplace.com/forum/smileys/Ermm.gif The two p-strokes, , a non-turbo 7.3, and a 6.5 dont do it and my buds new lly doesnt do it either....

Are you referring to the Tensionor Arm Pully?