Unidentifiable noise *Video* (1 Viewer)

[Igoteyedeas]

Alright guys, so after days of scouring the internet (largely this forum) I've reached my wits end trying to source what is causing this sound. Due to my work schedule I haven't had a chance to start removing parts to check them, but was hoping that you guys might be able to help me narrow down the cause so I can start wrenching in the right place.

So now the known symptoms:
• Sounds to me like it's coming from the front half of the vehicle
• Only appears after driving for 5-10 mins and reaching operating temps
• Seems to only occur in 1st, 2nd at about 2,000rpm
• Can be faintly heard when revving in "P", but is magnified when putting the engine under load
• Transfer case, and F/R diffs all have new fluid (Front diff was replaced ~6k miles ago with a used unit though after I blew my original 2-pinion front diff)

After going through many different posts on the 80/100 forums, it seems like people have had similar issues but the symptoms aren't exactly what I'm experiencing. That said, it seems like possible culprits could be fan clutch, pinion bearing, or possibly belt tensioners going bad?

Driving in 2nd:


In "P" revving - you can slightly hear it:


Hoping someone with more knowledge than me has heard this sound before! Thanks in advance guys.

 

[Igoteyedeas]

I should also note: I'll be driving to the mountains tomorrow so I should be able to get some more data on what loads/RPM/speeds cause this, but I'm hoping the info and examples above can help you guys develop an educated guess. Thanks!

 

[Evan Kapel]

Sounds to me like you are driving over railroad ties. Does it make the same noise on the road?
The whining sound sounds like trans/differential wear
and since it only happens in 1st/2nd my guess a trans issue although I am no expert. You advertise your
location as LBC which must mean Lower British Columbia or Long Beach California or Laguna Beach California
although with the palm trees in your video it is probably Laguna Beach! I know I have not told you anything
you don't already suspect but I will be interested in what the noise turns out to be.

 

[Igoteyedeas]

Sounds to me like you are driving over railroad ties. Does it make the same noise on the road?
The whining sound sounds like trans/differential wear
and since it only happens in 1st/2nd my guess a trans issue although I am no expert. You advertise your
location as LBC which must mean Lower British Columbia or Long Beach California or Laguna Beach California
although with the palm trees in your video it is probably Laguna Beach! I know I have not told you anything
you don't already suspect but I will be interested in what the noise turns out to be.

Yeah, I suppose that was a rough residential street take that video on. Well, that and my damn OME suspension that rides like a rock!

At any rate, I was thinking trans for sure, but since the noise can be faintly heard when in "P", that makes me think it's engine related? Also, LBC is Long Beach, CA

 

[87warrior]

Is your intake tube/airbox sealed up? The noise kind of sounds like a whistle that is occurring when the engine starts to load up.

 

[Igoteyedeas]

Is your intake tube/airbox sealed up? The noise kind of sounds like a whistle that is occurring when the engine starts to load up.

That's a great question. Visually I would say yes as everything is tightened, but that rubber/plastic intake arm is nearly 20 years old so it may have a hairline that's causing the air being pulled in to whistle.

I've also noticed (as of today) that I have a snapped bolt on my passenger side exhaust flange where it connects to the catalytic convertor. Perhaps that's why the engine warming up is a factor because the metal expands and creates a small gap for air to escape (and subsequently whistle)? Is that a thing?

On that note: Any one had a similar issue re: the exhaust flange bolts where the exhaust manifold connects to the cat? Haven't been able to find a replacement part listed on Toyota, but also not sure as to the size/thread pitch I should be looking for. Thanks!

 

[Evan Kapel]

i agree with you and 87 warrior that either could be the source but if it is only happening in 1st and 2nd maybe
it is in the drivetrain. I could not hear it in the stationary video. I could hear intake noise, which sounds different than
the whine in the 1st video. If you do replace the exhaust bolt be sure to use a JIS metric bolt as in my
experience standard metric fasteners use too coarse a thread.

 

[NMjr]

Sounds similar to when I needed a new alternator. Have you replaced yours recently?

 

[NMjr]

I should also note that the whine my truck would make was intermittent as well

 

[Somebodyelse5]

sub'd. mine does this also...Replacing alternator, fan clutch, and tensioner pulley did not cure the noise.

 

[Igoteyedeas]

I should also note that the whine my truck would make was intermittent as well

No, it’s been on the truck since I bought it with 230k on it, so who knows how old it is. Given how oddly intermittent it is, that could absolutely be a source. Did you notice yours making noise at specific RPMs?

 

[mmaakk]

I had a similar sound and turned out to be the fan bracket, intermittent but got worse with time... I thought it was the fan clutch or tensioner but no. I had about 280k miles when it went out.

 

[Julian Stead]

Remove the serp belt and see if it goes.

 

[Biga27110]

Alright guys, so after days of scouring the internet (largely this forum) I've reached my wits end trying to source what is causing this sound. Due to my work schedule I haven't had a chance to start removing parts to check them, but was hoping that you guys might be able to help me narrow down the cause so I can start wrenching in the right place.

So now the known symptoms:
• Sounds to me like it's coming from the front half of the vehicle
• Only appears after driving for 5-10 mins and reaching operating temps
• Seems to only occur in 1st, 2nd at about 2,000rpm
• Can be faintly heard when revving in "P", but is magnified when putting the engine under load
• Transfer case, and F/R diffs all have new fluid (Front diff was replaced ~6k miles ago with a used unit though after I blew my original 2-pinion front diff)

After going through many different posts on the 80/100 forums, it seems like people have had similar issues but the symptoms aren't exactly what I'm experiencing. That said, it seems like possible culprits could be fan clutch, pinion bearing, or possibly belt tensioners going bad?

Driving in 2nd:


In "P" revving - you can slightly hear it:


Hoping someone with more knowledge than me has heard this sound before! Thanks in advance guys.

I have the same sound thats intermittent does anyone have any idea what it could be? Ive replaced the idler, tensioner pulley and the serp belt. My research says it could either be a fan clutch or alternator whine. My alternator works fine though and fan clutch seems to work.

 

[Igoteyedeas]

I have the same sound thats intermittent does anyone have any idea what it could be? Ive replaced the idler, tensioner pulley and the serp belt. My research says it could either be a fan clutch or alternator whine. My alternator works fine though and fan clutch seems to work.

Fan clutch was on its way out and ended up completely seizing a few months later. Replaced with a new OEM unit and everything is golden!

 

[Biga27110]

Fan clutch was on its way out and ended up completely seizing a few months later. Replaced with a new OEM unit and everything is golden!

I KNEW IT! Thank you so much