Jump to content

Recommended Posts

Posted (edited)

Howdy.  About a year ago my 2015 2500HD 6.0L flex fuel developed a loud squeal on the first startup of the day.  Only happens on the first startup even if the truck sits for a long while after the first startup.  I have changed the serpentine belt, tensioner pulley and the idler pulley.  Still there.  I tried listening with one of those stethoscope thingies but the radiator fan is too loud.  Before I take it to a stealer, what else can I troubleshoot?  Thanks!

 

Here's a link to a video on facebook.  Not sure how to post it directly here.

 

https://www.facebook.com/100004961733954/videos/493003216698713/

 

Edited by corn18
Posted
1 minute ago, corn18 said:

Howdy.  About a year ago my 2015 2500HD 6.0L flex fuel developed a loud squeal on the first startup of the day.  Only happens on the first startup even if the truck sits for a long while after the first startup.  I have changed the serpentine belt, tensioner pulley and the idler pulley.  Still there.  I tried listening with one of those stethoscope thingies but the radiator fan is too loud.  Before I take it to a stealer, what else can I troubleshoot?  Thanks!

IMG_5967 3.MOV

 

 

Have you taken the belt off and started it briefly?  Don't leave it running long as the water pump won't be spinning, so maybe 10-20 seconds quick to see if the noise goes away.  If its gone, could be a bad water pump. 

 

If the noise is still there without the serpentine belt on, I'd remove the AC compressor belt and retest, see if the noise goes away.  If it goes away after that, its the AC compressor.

 

If the noise is present with either belt off, you've got an internal issue like a lifter spun in the bore.   

  • Like 1
Posted
2 minutes ago, newdude said:

 

 

Have you taken the belt off and started it briefly?  Don't leave it running long as the water pump won't be spinning, so maybe 10-20 seconds quick to see if the noise goes away.  If its gone, could be a bad water pump. 

 

If the noise is still there without the serpentine belt on, I'd remove the AC compressor belt and retest, see if the noise goes away.  If it goes away after that, its the AC compressor.

 

If the noise is present with either belt off, you've got an internal issue like a lifter spun in the bore.   

Coolio.  Will try that in the morning.  Can only troubleshoot one thing a day.

 

Posted (edited)
On 8/14/2024 at 12:31 PM, newdude said:

 

 

Have you taken the belt off and started it briefly?  Don't leave it running long as the water pump won't be spinning, so maybe 10-20 seconds quick to see if the noise goes away.  If its gone, could be a bad water pump. 

 

If the noise is still there without the serpentine belt on, I'd remove the AC compressor belt and retest, see if the noise goes away.  If it goes away after that, its the AC compressor.

 

If the noise is present with either belt off, you've got an internal issue like a lifter spun in the bore.   

Ok, finally got around to this.  I removed the serpentine belt and started the truck.  No squeal or odd noises, so the air conditioner compressor is not the source.  Replaced the serpentine belt and the squeal was there.  I also removed the clutch fan and the squeal was still there.  So I guess it is either the water pump or the power steering pump.  I did turn the steering wheel and the squeal did not change so would my best bet be to change the water pump?

Edited by corn18
Posted
1 hour ago, corn18 said:

Ok, finally got around to this.  I removed the serpentine belt and started the truck.  No squeal or odd noises, so the air conditioner compressor is not the source.  Replaced the serpentine belt and the squeal was there.  I also removed the clutch fan and the squeal was still there.  So I guess it is either the water pump or the power steering pump.  I did turn the steering wheel and the squeal did not change so would my best bet be to change the water pump?

 

 

Yea sounds like its the water pump.  I assume you left the AC belt on as its a separate belt on these engines so if it was quiet without the main belt you can rule the AC out yes.

 

 

Posted
16 minutes ago, newdude said:

 

 

Yea sounds like its the water pump.  I assume you left the AC belt on as its a separate belt on these engines so if it was quiet without the main belt you can rule the AC out yes.

 

 

Yup, left the belt on the ac when I removed the serpentine belt.  I'll replace the water pump and go from there.  Thanks!

Posted

Ok, replaced the water pump and the squeal seems to have gone away.  Will have to wait until tomorrow morning to know for sure but I am hopeful.

Posted

Replaced the power steering pump.  The power steering fluid was very dark and smelled bad.  Steering is easier now as well.  So maybe that was the problem all along.  Will see tomorrow AM when I start the engine cold.

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
  • Latest Articles

  • Posts

    • I had an 88 K1500 with a 5.7 that had those symptoms, I know totally different, it ended up being the ECM. Once you get the fuel system fixed if it still runs lousy you may want to investigate that. it didn't set any codes, stalled ,ran rough at times etc
    • Congratulations Isttype, on your gmc. Really like my 2024 2500hd sle doublecab now with 85,500 miles.  I checked the oil today at 4800 miles since last oil change and barely reading on the stick.  I don't care if GM says it's Acceptable adding a quart every 2000 miles because that is 100% BS, It is not a 1966 Harley Shovelhead! Sounds like it's setting up a future failure like I had with my 1500 6.2l. Other than oil consumption problems, I really like the 6.6l gas and 10 speed is really nice.  Towed a light 4000 pound trailer last week and averaged 14 mpg.  I was pretty impressive that a 7300 pound gas truck did 14mpg towing, Later-
    • Long Term Cold Cycle Limited Testing   Back to the 1990's and XOM's million mile test. Since then there have been others and there will be more. Schaeffer's, AMSOIL to name two. Of these Schaeffer's is the stand alone which I will explain in a bit later.    http://papers.sae.org/600190/:   http://papers.sae.org/850215/:   Up to 75% of  engine wear occurs on cold starts. These two links (above) provide the technical reasons for engine wear. In a nut shell, and by a large margin, cylinder wear is what takes out most motors and even with a pre-oiling system that part of the engine is dry enough on cold starts and cold warm up to pierce Stribeck.   So when you put a motor, or a car, on a dyno for a million miles stopping only for oil changes, (yes fuel is uninterrupted) or break down maintenance, you are depriving the test of the most important part of it's wear cycle. Yes a million is then a pretty easy walk even for a mineral oil under those conditions.    How about cleanliness during the long test cycles? Same thing. Varnishes that stick rings and insulate parts are laid down by repetitive 'heat cycles'. It's the cool down the precipitates the varnishes. These long runs also hinder acidic attack caused by cold start richness and less than optimal cold start ring sealing. They hinder water formation and enhance breathing of the crankcase; the petri dish of acid formation, the first step in sludge formation, amalgamation and precipitation. These motors are also monitored and controlled for water and oil temperatures to within the "normal operating range".      https://www.swri.org/sites/default/files/sequence-iiih-test.pdf Note the test sequence in some boutique oils literature for testing, API IIIH, is not the standard used for the ILSAC G7 testing. Does that mean it is irrelevant? No, not as used. As used as a 'visual guide' it makes it's point. The G7 weighted piston deposit minimum is lower.      Back to Schaeffer's. That was a cyclical test of an engine in fleet service and not a dyno mule and if you saw the video it was not mirror clean but wear was low.    There are oils like BioSyn and other 'Renewable" source oils that taught cleanliness and have proven themselves in fleet testing. Havoline an other example.    The newest ILSAC G-7 test prioritize cleanliness, LSPI mitigation and fuel economy OVER WEAR. In comparison Porsche C30 Specification Verses ILSAC G-7 Specification below:      Some will balk that this graph isn't apples to apples and I will challenge that in that this graph represent the SPECIFICATION and not the any One Oil Performance.   It is absolutely possible to minimize wear, maximize cleanliness and mitigate LSPI etc., It just isn't cheap and currently I see none that are not walking toward profit over performance.     
    • I don't think you will need a split, separate product, etc., the OBD port should be able to deliver everything you need. Since your device would be plugged into it all the time, it wouldn't miss anything.    Hardware in this case will be the easiest part of your project - ELM 327 devices will already deliver all the data you need. Reporting/software is where your advantage/marketability is.
    • I do too. I’ll never be stuck again 😂
  • GM-Trucks.com Clubs

  • Popular Contributors

×
×
  • Create New...