6 speed rattle/noise at 3k RPMs

[opiop]

Hey all, just started noticing a noise coming from the transmission/pedal area in my 6 speed JL. It seems to happen on flat ground or inclines, so load doesn’t seem to matter. It’s always around 3k RPMs and I only notice it in 2nd or 3rd gear (might happen in the higher gears but wind noise is too loud and would mask it). I can’t consistently reproduce it, seems to happen fairly randomly.

Any ideas?

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[fdFifty]

Hey all, just started noticing a noise coming from the transmission/pedal area in my 6 speed JL. It seems to happen on flat ground or inclines, so load doesn’t seem to matter. It’s always around 3k RPMs and I only notice it in 2nd or 3rd gear (might happen in the higher gears but wind noise is too loud and would mask it). I can’t consistently reproduce it, seems to happen fairly randomly.

Any ideas?

Hard to tell from just the video but it seems like it's something that's rattling from resonant vibrations instead of a bad bearing or unbalanced flywheel. Could totally be wrong though. Do your brake or clutch pedals seem to have excessive side to side play?

 

[opiop]

Just checked, and the pedals still feel solid. Looks like I just need to take it to the dealer (again). This is like the 5th or 6th issue it’s had, starting to get tired of it.
Thanks for the suggestion, wish it were that simple!

 

[Petey]

Hey all, just started noticing a noise coming from the transmission/pedal area in my 6 speed JL. It seems to happen on flat ground or inclines, so load doesn’t seem to matter. It’s always around 3k RPMs and I only notice it in 2nd or 3rd gear (might happen in the higher gears but wind noise is too loud and would mask it). I can’t consistently reproduce it, seems to happen fairly randomly.

Any ideas?

Anything done to the exhaust? .. it's a bit more throaty then mine sound kinda cool.

 

[opiop]

Anything done to the exhaust? .. it's a bit more throaty then mine sound kinda cool.

Nope, stock 3.6l exhaust!

 

[Lab1]

Nope, stock 3.6l exhaust!

Mine does this too randomly but I think it’s something inside the dash that is vibrating. It isn’t mechanical so I’m not worried about it.

 

[opiop]

Mine does this too randomly but I think it’s something inside the dash that is vibrating. It isn’t mechanical so I’m not worried about it.

Yeah, mine hasn't done it in a while so I'm not too worried about it. I think you're right that it's something inside the dash, or at the very least I don't think it's something related to the engine. If it starts making the noise again I'll take it to the dealership but for now I'm not worried.

 

[Dp227]

Have any additional thoughts on this one? 3.6 6MT and having the same noise at nearly exactly 3k rpm. I tried to get a video tonight and of course after a restart, it didn’t do it again. I’ve gotten one previously. I’ll see if I can find it.

Update: found the previous video. Not particularly worth sharing. Will try for another.

I’m fully willing to admit it might be some sort of vibration that only happens at 3k rpm, but it’s certainly odd.

 

[Stuckinthesand]

https://www.jlwranglerforums.com/forum/threads/rattling-upon-acceleration.10007/

Lots of reading. In essence it seems to have to do with the tune from the factory. Affects autos and manuals.

 

[LatteSipper]

@opiop or @Dp227 Did you find the source of this or solve it at the dealer? My 2021 has the exact same behavior (3k rpms most notably in 2nd and 3rd gears) and same noise.

 

[Dp227]

@opiop or @Dp227 Did you find the source of this or solve it at the dealer? My 2021 has the exact same behavior (3k rpms most notably in 2nd and 3rd gears) and same noise.

I haven’t yet. Still thinking it’s the engine, not vibration. I’ve been watching off road pages per some suggestions here. It does seem to really only occur when the engine temp is over 2xx. Trying to figure out what that number is. Going for a decently long drive this weekend. Will see.

Edit: to be clear, the behavior gear and RPM wise is exactly what you describe. 6MT or automatic?

 

[colby]

Mine does the same thing. It’s more noticeable on hills in a similar RPM range. I have the 8 speed and V6.

 

[Dp227]

Mine does the same thing. It’s more noticeable on hills in a similar RPM range. I have the 8 speed and V6.

Don’t you love how the Manila has an out and says this is “normal”?!

it’s been posited that it’s running too lean. NGL, I tend to believe that since it seems temperature based from what I can tell.

To Be clear though, I’m far from a mechanic… well, maybe an inept one…., and correlation doesn’t necessarily equal causation.

 

[LatteSipper]

Since posting a few days ago, I’ve been chatting with another member through DM. He and I both confirmed the noise/rattle at 3k stops when putting light pressure on the clutch pedal, not enough to depress the pedal.

It seems something in that assembly vibrates at 3k in just the right way to make the sound, when warmed up. I’ve reproduced it in gears 1-3, but can’t hear it in 4th (if it does occur) over the wind noise. I even lightly tapped the brake pedal when occurring and it is not that pedal, it is confirmed in the clutch pedal assembly.

In my case, it isn’t consistent. Yesterday for example, it didn’t occur. This weekend it was consistently occurring.

 

[mwilk012]

Sounds like everyone here is describing a fuel knock problem.

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