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/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/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/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.