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2006 chevy trailblazer_ls
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705 Posts
Discussion Starter · #1 ·
When I start my truck it sounds great, virtually silent idling, however as I accelerate it whine constantly, changing pitch with acceleration. Truck has 48K on it. I've only had it 3 months, so I'm not sure what maintenance was ever done on it, not much I'd say judging from stuff like the OEM air filter it still had when I bought it. Would the transfer case or diff whine like that? I know the TC is coming due for service any day now and I believe the diffs should have been done before now. Any ideas?
 

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2004 gmc
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26,181 Posts
TC and diffs are all suspects, as are the PS pump, AC compressor, alternator, tensioner pulley and (ESPECIALLY) the idler pulley. The idler pulley (search for it) is super cheap and trivial to swap as an experiment.

It doesn't sound like a airflow whistling, does it?

Any different upon accel, coast, or decel?
 

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2006 chevy trailblazer_ls
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Discussion Starter · #3 ·
I'll take it for a little ride tonight when i get home to see if there's a difference, but as far as I recall its only on accel. I did read the several threads about the idler and tensioner pulleys, but that would whine in park or nuetral as well correct?
 

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2006 chevy trailblazer_ls
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705 Posts
Discussion Starter · #5 ·
ok, so when i got home i went out and fired up the TB and had the wife come out and give it some gas while i stood up front with the hood up, and my bad, it does do it when its not in gear, just couldn't hear it from inside the truck. So it most likely is idler, but definitely something on the serpentine belt. Oh well, that's why I bought it certified. I'll take it as soon as i get a chance
 

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2003 chevy trailblazer_lt_ext
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967 Posts
Mine does something very similar. Turn your wheel from left to right a few times. If the whining gets louder, it may very well be your PS Pump. Not a very common issue on a TB, but I've heard one or two others that had the same problem.
 
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