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-   -   New 2012 WK2 Pentastar 3.6 - Downhill Whine (http://www.jeepgarage.org/f108/new-2012-wk2-pentastar-3-6-downhill-whine-32451.html)

Sigma 12-12-2011 11:40 AM

New 2012 WK2 Pentastar 3.6 - Downhill Whine
 
Hello Guys,

Just got my new jeep and love it! Looks like a knowledgeable group here. But I do have a question: I'm at about 500 miles just breaking in and have noticed a high pitched whining noise in auto mode when off the gas and going downhill at 35-40 or so. It doesn't happen all the time and I didn't notice the sound in sport mode. It sounds like it may be from the transfer case. Do you guys think that this will go away or is it something I should be worried about?

Thanks.

Jimbo 12-13-2011 08:25 PM

Re: New 2012 WK2 Pentastar 3.6 - Downhill Whine
 
I had a similar problem at highway speeds. The occurs between 60-75 mph when my foot is off the gas. Is whine very high pitched?

Sigma 12-14-2011 12:40 AM

Re: New 2012 WK2 Pentastar 3.6 - Downhill Whine
 
Jimbo,

Yes, the noise is pretty high pitched and almost sounds like the wind. Not so much like a gear whine, though. The noise is especially noticeable when going downhill with foot off the gas. Since my first post, I just got back from a road trip for some breaking in. I now have just over 1000 miles on it and it seems like things have freed up a bit. The noise is still there but has become more faint and is shorter in duration. It doesn't seem to last last longer than several seconds after I lift the foot off the gas. But it's still there, also at higher speeds like 55-65. If I accelerate, it dissappers. Maybe it's just normal behaviour and the 4x4 transmission just needs more breaking in? What do you think? Comments anyone?

BTW, this is my 3rd JGC, I have a 96 ZJ and a 2009 WK. Jeep hit a home run with the WK2! My only complaint so far, is that there seem to be some holes when accelerating uphill out of low rpms. Think that could be fixed very well with a six speed. But with all that shifting in a six speed, would the transmission last that long? Not sure.

hammer1234 12-14-2011 06:49 AM

Re: New 2012 WK2 Pentastar 3.6 - Downhill Whine
 
Quote:

Originally Posted by Jimbo (Post 533504)
I had a similar problem at highway speeds. The occurs between 60-75 mph when my foot is off the gas. Is whine very high pitched?

What was the fix? I get a brief whine under light throttle at highway speeds but it's not continuous.

Sigma 12-14-2011 10:47 AM

Re: New 2012 WK2 Pentastar 3.6 - Downhill Whine
 
Quote:

Originally Posted by hammer1234 (Post 533737)
What was the fix? I get a brief whine under light throttle at highway speeds but it's not continuous.

I think I read a post from Jimbo where the whine went away by itself???

hammer1234 12-14-2011 12:39 PM

Re: New 2012 WK2 Pentastar 3.6 - Downhill Whine
 
Quote:

Originally Posted by Sigma (Post 533833)
I think I read a post from Jimbo where the whine went away by itself???

Wish all of the odd noises I've had did that...

Jimbo 12-14-2011 01:51 PM

Re: New 2012 WK2 Pentastar 3.6 - Downhill Whine
 
Apparently, your whining noise is disappearing as more miles are accumulated on the Jeep. This is very similar to my situation. As far as the holes in the acceleration, I believe that the transmission is programmed to shift in the higher gears too early. Therefore, reducing the engine's pickup. The dealer should reprogram this for delayed upshift.

Sigma 12-14-2011 02:43 PM

Re: New 2012 WK2 Pentastar 3.6 - Downhill Whine
 
Quote:

Originally Posted by Jimbo (Post 533988)
Apparently, your whining noise is disappearing as more miles are accumulated on the Jeep. This is very similar to my situation. As far as the holes in the acceleration, I believe that the transmission is programmed to shift in the higher gears too early. Therefore, reducing the engine's pickup. The dealer should reprogram this for delayed upshift.

Early upshift probably for mileage reasons?

Jimbo 12-14-2011 05:07 PM

Re: New 2012 WK2 Pentastar 3.6 - Downhill Whine
 
Most likely for better gas milage. Try the sport mode to see if there is a difference

Jimbo 12-19-2011 11:06 AM

Re: New 2012 WK2 Pentastar 3.6 - Downhill Whine
 
Sigma,

Do you still have the high pitched whine going down hill?

Palmetto 12-30-2011 08:06 PM

Re: New 2012 WK2 Pentastar 3.6 - Downhill Whine
 
I have a similar light/no throttle high pitch whine. Seems to be present mainly at 60 - 80 mph. Most noticeable when cruising on a flat stretch of interstate. Now have about 850 miles, seems like it may be getting better, but that could be wishful thinking on my part.

Perhaps mine is just transfer case whine? (QTI only on mine)

Sigma 01-04-2012 02:19 AM

Re: New 2012 WK2 Pentastar 3.6 - Downhill Whine
 
Mods: how did this thread get moved to "Engine Performance....."


Quote:

Originally Posted by Jimbo (Post 536544)
Sigma,

Do you still have the high pitched whine going down hill?

Jimbo, I still have the whine at about 65 when going off throttle and only in auto mode, not in sport. Sounds like it's not an isolated issue, Palmetto has the same thing going on. I'm now at about 1250 miles and it's still there. I hope it goes away over time.

Anyone with connections to the factory on this board?

Thanks!


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