Let's play "what's that noise?"

[joneseyyy]

So fellas...I've noticed lately a drivetrain whine under load. In drive, reverse, neutral, park. When the truck is cold and when warmed up. Had Scott remove the aux belt temporarily and the noise was unchanged, so it's not the alternator, PS pump, pulleys, or tensioners. Dealers first pass is that it might be the tranny front pump. Other ideas include timing chain guides worn.

Tranny was just serviced at 87k (BG flush). Noise was present before and after. FYI have serviced the tranny, tcase, and diffs at 30k intervals so not like its been neglected. Oil changes every 5k too.

Taking it to the dealer 2 hours away where I know the GM on Thursday to get to the bottom of it and pray my platinum warranty comes through!

Drives and shifts like nothing is wrong, btw.

 

[NYRunner]

I had the same thing and it was a bad front wheel bearing that was covered under my extended warrantee~

Hope that helps, and I can't believe I beat 1e, antman, Gary and the rest of the pros to the punch! =)

Happy New Year everyone!!!

 

[Biggcrisp]

Mine does to....I think mine is normal.

I have to try to hear it because it's not loud. Can really hear it when heavy on the throttle. Not something I'm concerned about other than it's a clue to not be in a rush (while towing).

Same noise my fj and the wife's highlander made under load.

 

[Jesse1983]

Sorry, Ben I don't have a guess on your noise. But I like your thread title so much that I'd like to throw my noise in the mix.

I started noticing it after a heavy snow and a decent amount of 4wd usage. I can hear a clunk from time to time while driving (specifically turning) which appears to be coming from the front right. I can duplicate the noise by driving about 5-10 mph, cocking the wheel hard left, and stomping the breaks. Truck is at the dealer for a diagnoses in the morning. Any guesses?

 

[NYRunner]

Well duh- never mind what I said... after rereading your post bearings would have no bearing when in park.

Yup.

It's Monday LOL

 

[Biggcrisp]

Sorry, Ben I don't have a guess on your noise. But I like your thread title so much that I'd like to throw my noise in the mix.

I started noticing it after a heavy snow and a decent amount of 4wd usage. I can hear a clunk from time to time while driving (specifically turning) which appears to be coming from the front right. I can duplicate the noise by driving about 5-10 mph, cocking the wheel hard left, and stomping the breaks. Truck is at the dealer for a diagnoses in the morning. Any guesses?

Only guessing! ICE? Of course I don't know whether you park in a heated environment or the ambient temps in your area.

 

[1engineer]

Ben if you have a whine even in park with the belt removed that means it can only be a few things. Not a bearing as that usually makes a growling noise. Does the whine change pitch with RPM?

 

[joneseyyy]

Ben if you have a whine even in park with the belt removed that means it can only be a few things. Not a bearing as that usually makes a growling noise. Does the whine change pitch with RPM?

The whine does change in pitch, similar in tone to a PS pump moan but maybe not quite as much. It is not super intrusive (hard to pick out with the radio on and drowned out with tire/wind noise above 50 mph). I definitely hear it when I accelerate and then let off the throttle; sounds like the whine lags the engine sound in dying down.

 

[1engineer]

The whine does change in pitch, similar in tone to a PS pump moan but maybe not quite as much. It is not super intrusive (hard to pick out with the radio on and drowned out with tire/wind noise above 50 mph). I definitely hear it when I accelerate and then let off the throttle; sounds like the whine lags the engine sound in dying down.

So now I'm playing the game lol: "OK Ben does this whine happen in park when revving the engine or does this whine only happen when driving?" "Follow up question please Ben: Do you know what helical gear backlash sounds like?" Does the whine sound like that?" "If not, maybe you know what square cut gear whine sounds like, or maybe a supercharger type of whine?" I know, too many questions but I am just trying to narrow it down.

 

[harper7]

The whine does change in pitch, similar in tone to a PS pump moan but maybe not quite as much. It is not super intrusive (hard to pick out with the radio on and drowned out with tire/wind noise above 50 mph). I definitely hear it when I accelerate and then let off the throttle; sounds like the whine lags the engine sound in dying down.

Maybe buy or find someone that has a Electronic Stethoscope: Automotive or Mechanic's Stethoscope to help pinpoint the noise to engine or transmission. These dual vvt-i engines do have 3 timing chains and 4 timing gears that will probably whine some with wear over time. That doesn't necessarily mean there is anything wrong with them though and they might whine as they loosen up with chain/ gear wear.
Garage Essentials 2 - Mechanics Stethoscopes (diagnose bad injectors, bearings, ect...) - YouTube

They do make high dollar wireless stethoscopes called sonic analyzers that some race teams have and they use software to compare noises to known good drivetrains and suspensions.

Good luck Ben!:zoom:

 

[Jeremy556]

Definately get a stethoscope and check timing cover, valve covers, and externally visible pumps.
Only cams I have known to whine were all straight gear driven, and always whine. Usually when a timing chain tensioner wears out, you get a clacking noise at a certain RPM range.
I'm thinking a chain driven or electric pump.

 

[Scott@Hightech]

Definately get a stethoscope and check timing cover, valve covers, and externally visible pumps.
Only cams I have known to whine were all straight gear driven, and always whine. Usually when a timing chain tensioner wears out, you get a clacking noise at a certain RPM range.
I'm thinking a chain driven or electric pump.

No "normal" timing chain noises. However the noise was louder at the front of the engine than the rear.

So now I'm playing the game lol: "OK Ben does this whine happen in park when revving the engine or does this whine only happen when driving?" "Follow up question please Ben: Do you know what helical gear backlash sounds like?" Does the whine sound like that?" "If not, maybe you know what square cut gear whine sounds like, or maybe a supercharger type of whine?" I know, too many questions but I am just trying to narrow it down.

Will happen in any gear, moving or not. Sounds more like a square cut gear noise.


The noise was loudest behind the water pump(center of the engine). I suggested timing chain noise of some sort. The dealer said something about the trans front pump. That is possible, i have seen noises travel through the car and appear to come from another place. But the noise only changes with RPM and does not change based on load. Most Front pump failures that i have seen the noise changes with load.

 

[1engineer]

The whine does change in pitch, similar in tone to a PS pump moan but maybe not quite as much. It is not super intrusive (hard to pick out with the radio on and drowned out with tire/wind noise above 50 mph). I definitely hear it when I accelerate and then let off the throttle; sounds like the whine lags the engine sound in dying down.

No "normal" timing chain noises. However the noise was louder at the front of the engine than the rear.



Will happen in any gear, moving or not. Sounds more like a square cut gear noise.


The noise was loudest behind the water pump(center of the engine). I suggested timing chain noise of some sort. The dealer said something about the trans front pump. That is possible, i have seen noises travel through the car and appear to come from another place. But the noise only changes with RPM and does not change based on load. Most Front pump failures that i have seen the noise changes with load.

Hmmm. If it were my truck, I would get a new timing chain and water pump installed. You are getting close to the mileage anyway and you are the definition of "severe duty" haha! The good thing about doing it now is:
1. You will see if either of these is the culprit
2. You can check other items closer while doing this service
3. You gotta do it anyway soon

The bad thing is cost. Bottom line though if you are hearing a whine that was not there before and you did not install a new custom cut differential, supercharger or blower then it's usually a warning sign! Good luck Ben and Scott!

 

[joneseyyy]

Hmmm. If it were my truck, I would get a new timing chain and water pump installed. You are getting close to the mileage anyway and you are the definition of "severe duty" haha! The good thing about doing it now is:
1. You will see if either of these is the culprit
2. You can check other items closer while doing this service
3. You gotta do it anyway soon

The bad thing is cost. Bottom line though if you are hearing a whine that was not there before and you did not install a new custom cut differential, supercharger or blower then it's usually a warning sign! Good luck Ben and Scott!

We will see, the dealer is going to dig into it starting Friday and they'll have the truck for almost a week while I'm on the West Coast. My understanding is the timing chain(s) on our trucks is not really built as serviceable parts, so getting to them is super labor intensive ($$$). We shall see...

 

[Ducmonsta]

We will see, the dealer is going to dig into it starting Friday and they'll have the truck for almost a week while I'm on the West Coast. My understanding is the timing chain(s) on our trucks is not really built as serviceable parts, so getting to them is super labor intensive ($$$). We shall see...

Ben, I'm assuming this is the same dealer that replaced your ps pump? The gm has a modded fj?

Hmmm. If it were my truck, I would get a new timing chain and water pump installed. You are getting close to the mileage anyway and you are the definition of "severe duty" haha! The good thing about doing it now is:
1. You will see if either of these is the culprit
2. You can check other items closer while doing this service
3. You gotta do it anyway soon

The bad thing is cost. Bottom line though if you are hearing a whine that was not there before and you did not install a new custom cut differential, supercharger or blower then it's usually a warning sign! Good luck Ben and Scott!

Greg, could you direct me to where this service is recommended by mileage? I went through the fsm and it only goes to 120k. I wasn't aware that our trucks timing chain needed to be serviced similarly to a timing belt.

 

[1engineer]

Ben, I'm assuming this is the same dealer that replaced your ps pump? The gm has a modded fj?



Greg, could you direct me to where this service is recommended by mileage? I went through the fsm and it only goes to 120k. I wasn't aware that our trucks timing chain needed to be serviced similarly to a timing belt.

You are absolutely right Bobby. I should have re read my post before submitting! There is no real documentation on timing chain life. It should really outlast your engine in this application. So forget I said "It's almost time" because in reality there is none. The problem is the whine and I was concentrating on that instead of being clear. The only other way I know to create a whine, other than gears, that is RPM dependent is fluid or air flow across an orifice. This leads back to fuel or intake though. Most of the time those create a whistle more so than a whine. Scott says it has the whine of a square cut gear and that is pretty distinctive. You have any ideas?

 

[joneseyyy]

Hey Bobby, yep its the same dealer that did the PS pump. I talked through it with the GM and am pretty confident that whatever it is will get covered in the warranty. Never a guarantee, though.

 

[Antman]

I may have the same noise... It's a whine, like a gear whine, RPM dependent. Seems to be more prevalent during colder weather (but not entirely). Not too loud at all. That sound like your noise?

To me, mine sounds like a PS pump or alternator- but if yours makes the noise without the belt it can't be...

I'm curious to see what the dealer finds out.

 

[joneseyyy]

I may have the same noise... It's a whine, like a gear whine, RPM dependent. Seems to be more prevalent during colder weather (but not entirely). Not too loud at all. That sound like your noise?

To me, mine sounds like a PS pump or alternator- but if yours makes the noise without the belt it can't be...

I'm curious to see what the dealer finds out.

Yeah, I'm curious as hell too. That's the thing, its not a alien noise, but more of a whine than the motor used to make! Scott listened to mine and Swimmerdude's side by side, and there was a noticeable difference. of course I have about 80K more miles on the motor.

 

[joneseyyy]

Well, she's dropped off at Steven Toyota in Harrisonburg. They're going to start troubleshooting tomorrow. Meanwhile I'm off to San Francisco tomorrow and trying to put it in the back of my mind.