2015 Jku with 65k miles. 5k, 5w 20 synthetic ultra plat penzoil oil changes with a stock filter. I run a snorkel with a better breather intake tube, also run a catch can. Stock air filter with just simple tuner and a catback exhaust. Nothing crazy and the engine has never been opened up, on stock coil packs and spark plugs. Seemingly coming from the driver side bank? Though it doesn't sound metallic like rocker arms when they go out, almost like a buzz. This was a cold start at 40 degrees and i only noticed it when i lifted my hood to add windshield wiper fluid.

 

That sounds like the alternator, but from the video it sound3d loudest when you were pointing at the top of the motor. Would therefore get a mechanics stethoscope and start probing, though I would be listening around everything connected to the serpentine belt.

 

I'm having a hard time hearing what you're referring to, though I'm on a crap chromebook that doesn't have the best audio. I'd agree that a mechanics stethoscope and probing is in order. Having just replaced my rocker arms I know that sound is hard to mistake so I have no doubt it's something else if you think the sound doesn't match. Also, that is a sound that is easily distinguishable with the hood closed from 50' away IMO.

I thought this as well, though I took videos before my rocker arm repair and after......and even the after videos that 3.6L engine is just loud in general when close up and I think it's accentuated even more on video. I'm thinking maybe we're just distracted by that short bit of sound.

 

It sounds like a normal 3.6 IMO. It's not known to be a quiet engine.

 

Has this noise just got louder on you? Am I hearing the muffler sounds when it is idling there because if that is the case very hard to determine if there is a concern you should look at. Hard to be Dr Diagnose over the internet. Stetho and probe is your best bet but that makes any engine sound like it is falling to bits due to amplified everything.

 

Minnesota just hit winter, sub freezing temps in the night. Have not opened the engine since summer. Maybe im crazy

 

My battery cracked last winter, ill check it out. Thanks!

 

My steering pump went out 2 weeks ago, jeep doesnt idle steer well anymore. Seemingly only got louder when MN hit winter temps below freezing. Thanks!

 

Noise could be PS pump then. Are you running the right spec fluid in it. Not sure when you bought this Jeep but when I buy one the vehicle gets every fluid changed out immediately with high quality stuff - that is engine, rad, power steering, transmission, brake fluid, transfer case and diffs. Never been stranded yet!!

 

Just the stock transmission fluid atf+4. Im about to replace it with mopar atf+4 with the new pump ill put in