2005 Nissan Altima - The Serpentine belt shakes when I have the air/fan on AND I put the car in drive. It sounds fine when I'm in Park, but as soon as I put it in drive, the shaking begins and it squeals.

That isn't the way to do it. You should have a bypass pulley, which keeps the route and the angles and the same length belt.

Details of bypass and the serpentine belt diagram in the link

https://www.google.com/search?q=2006+Nissan+Altima.+Serpentine+belt+diagram+no+air+conditioning&tbm=isch&ved=2ahUKEwiT2pXX38H0AhWQsHIEHZE8ARMQ2-cCegQIABAA&oq=2006+Nissan+Altima.+Serpentine+belt+diagram+no+air+conditioning&gs_lcp=CgNpbWcQAzoHCCMQ7wMQJ1CQGliJTmC4aWgBcAB4AIABa4gBnwiSAQQxMi4xmAEAoAEBqgELZ3dzLXdpei1pbWfAAQE&sclient=img&ei=0femYdOtEpDhytMPkfmEmAE&bih=937&biw=1920&rlz=1C1QJDB_enCA643CA644

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How To Change The Serpentine Accessory Belt On Nissan Maxima Altima Etc

Nissan Drive Belt Tensioner and Belt Replacement 3 5 Front Wheel Drive

There are several videos on how to change out the serpentine belt For more info just do a web search " 2002 Nissan Altima serpentine belt replacement".

61.00 at dealer,54.00 at repair shop,20.00 to do it your self.Here's a link Ken on how to replace.Here's the belt you will need,takes about 15 minutes,better to do with 2 people,have to push tensioner to releave tension and other person removes belt,same as putting on.

Try a new fuel filter, and have your fuel pressure checked. Also , check for any stored diagnostic codes, in your engine computer.

I have the same problem. When my dealer changed my coolant I now seem to have a stuck thermostat. They are denying they did it. I haven't changed the thermostat yet but that is the problem.

the belt is the most likely culprit could also be the belt tension idler that puts tension to keep the belt adjusted

Hi,

Thanks for writing to Fixya.com.

Please find the steps to replace and install a serpentine belt for Nissan ultima.

http://www.ehow.com/how_6299871_install-serpentine-belt-nissan-altima.html
and
http://media.photobucket.com/image/serpentine%20belt%20for%202005%20nissan%20altima/harshreality001/Alternator%2011_26_2008/DSC01605.jpg


Thanks for contacting Fixya and please accept the solution if it has helped you.

sounds like you need to replace the idler pully and maybe the tens. pully. and that will solve your sounds problem. whats happening is the bearings are bad and thats what you hear

Notes Drive Belt Routing

yes its simple the best way is to get a DIGITAL CAMERA AND TAKE A PICTURE OF IT AND STUDY THE PICTURE WELL YOU WILL DO JUST FINE