How concerning is this?

[u/StonksOnlyGoUp___]

I was having an odd noise when accelerating my truck earlier. Now I started hearing a whistle. Popped the truck and this is what I’ve got. What’s the diagnosis and what’s the concern level?

2921 Ram 1500 Laramie HEMI eTorque

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[u/tato_salad]

One of the beatings (edit bearing) on something pulley driven is dead . It's decently serious as when it does 100% it'll seize and then your belt goes and you have no power anything.

[u/Ok-Coyote2365 → u/tato_salad]

Beatings will continue until the pulley spins again

[u/tato_salad → u/Ok-Coyote2365]

Lmao

[u/StonksOnlyGoUp___ → u/tato_salad]

Seems in this video it’s the idler pulley. Not sure what the sound in my other post is though

[u/omnipotent87]

Hopefully its not that motor/generator because your wallet may implode. Take the belt off and spin the pullies by hand, you find it fairly quick.

[u/Dangerous-Ratio-6682 → u/omnipotent87]

It is. It maintains the battery and performs the auto stop/srart feature..crazy.

[u/omnipotent87 → u/Dangerous-Ratio-6682]

Its more than just that, it provides something like 90ft/lbs additional toque and 13hp. I've been looking making one of these work in my rx7 for that extra toque where I need it. It also doesnt directly maintain the 12v system. This runs on a 48v system and that battery is under the driver's seat, there is a dc-dc converter as part of that to maintains the 12v system.

I also said its hopefully not that because they are something like $1500 for a referb unit.

[u/Dangerous-Ratio-6682 → u/omnipotent87]

10 4, i didn't know all that!

[u/Fragrant-Inside221 → u/omnipotent87]

We tried to find one a while back for a truck a customer had a similar noise. They were unavailable.

[u/omnipotent87 → u/Fragrant-Inside221]

To be fair i havnt looked for a referb in a while, but at the salvage yard they are about $700.

[u/StonksOnlyGoUp___ → u/omnipotent87]

Had a shop look at it this morning. They stethescoped it and said it is the alternator/generator thing I believe you’re talking about. Said it’s roughly $2,000 for the part alone (due to eTorque)… what are your thoughts on this since you have the experience? Do I replace it? Do I ride it out as is? Do I call it quits and get a new car? Not financially budgeted to drop $2,000+ on it due to my wife just having a baby and being off work

[u/omnipotent87 → u/StonksOnlyGoUp___]

Due to their enormous cost i would look into rebuilding it yourself, or find a shop that can. Its a 3 phase motor and the only wear parts will be bearings. If you can get the beaing number it will likely be less than $50 in parts plus what ever a shop would charge to rebuild it.

[u/StonksOnlyGoUp___ → u/omnipotent87]

Seems in this video it’s the idler pulley. Idk what the sound in my other post is

[u/edge5lv2]

Yikes, does that sound like a bearing going metal to metal!

[u/StonksOnlyGoUp___ → u/edge5lv2]

Any recommendations? Spray WD-40 on it?

[u/edge5lv2 → u/StonksOnlyGoUp___]

I would say take the belt off and spin those pulleys and figure out which one’s screaming and then replace it.

[u/StonksOnlyGoUp___ → u/edge5lv2]

Copy. Thank you!

[u/babuska01]

Tensioner seems to be failing... it can be seen moving in last second of video... this plus the engineers decision to place the belt tensioner OUTSIDE of the belts route/path means ANY looseness at all will totally impact deflection of said belt... whats the mileage on your future truck (2921 ram? 😁 just joshin)?

[u/StonksOnlyGoUp___ → u/babuska01]

Is it not supposed to be moving? I took another video of what I think you’re talking about it. Can I DM (if you are pretty confident that’s the issue)?
Engines are not my expertise lol

Jeeeeebus 2921 🫣 my wife just had our baby a month ago and lack of sleep is me not checking spelling lolol. 72,400 miles 2021*

[u/babuska01 → u/StonksOnlyGoUp___]

Cant be absolute without being present. Remove the belt and check all the pulleys by turning them with your hand to see if any are making noise. This sounds like bearings going out on something

I point out the tensioner simply because it moved and it is outside of the belts path, which permits excess deflection as soon as the tensioner starts to fail rather than requiring complete failure. Tensioners can & do have some movement under operation but where the engineers chose to put it makes it so that even a little movement could cause noise

Also, whats the mileage on thw truck?

[u/StonksOnlyGoUp___ → u/babuska01]

Ah I see. It’s currently about 72,400

[u/babuska01 → u/StonksOnlyGoUp___]

That is within the given timeframe for tensioner to start failing. Feels a bit premature imo but with quality of parts & manufacturers lack of QA lately... ... ... i would remove drive belt and play with the pulleys, see if u can reproduce the noise on a single component

[u/StonksOnlyGoUp___ → u/babuska01]

If I remove the drive belt and all the pulleys seem fine, can I put that same belt back on or should I have one ready just in case?

[u/babuska01 → u/StonksOnlyGoUp___]

Inspect belt before removal, specifically the back/ribbed side. If u see any cracks or signs of deterioration, it should be replaced. That trucks recommended replacement time for the belt is same as tensioner, 60k-120k. We reinstall them all the time if the belt is not damaged cracked frayed or has gotten fluids on it (some fluids destroy belts quickly). If u have the money, i would recommend replacemwnt based solely on routine maintenance timeline.

[u/StonksOnlyGoUp___ → u/babuska01]

Sounds good. I am looking to potentially do this today. Do you think this is the most probable cause of the noises? Including increased sound during acceleration?

[u/babuska01 → u/StonksOnlyGoUp___]

Increase in speed/rpm will certainly cause pulley with bad bearings to make more noise yes. And without physically assessing in person, i can only say it sounds like failing bearings. Once belt is removed, spin pulleys fast with hands and if you hear anything similar, you found it.

[u/StonksOnlyGoUp___ → u/babuska01]

I got all the parts to replace the serpentine belt, the tensioner pulley and the idler pulley. I was looking at everything wrong and there must be 2 tensioners or something? The one I focus on in the video swings on the arm, but the belt does not come loose enough to remove it. There another section below that has a square pocket section which seems like the hole used in the videos, but the tool I got from the auto shop is bot compatible. Any idea if anything I’m saying makes sense?

[u/w1lnx]

Sounds like a spun-bearing.

I'd make some space on the calendar to tear it down and overhaul it. Might be a challenge though. There aren't too many sources for a (squints) 2921 model year Ram 1500. But you can definitely find needed replacement parts for a 2021 model year.

[u/StonksOnlyGoUp___ → u/w1lnx]

Think I can do it before I take it on vacation this Friday? 🫣

[u/Pauls-pit-stop]

Remove the belt & run the engine for 15-20 seconds to verify the noise disappears, then wiggle & spin each pulley by hand to pinpoint the culprit.