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G56 Neutral Noise Question

Posted: Thu Sep 13, 2018 8:43 pm
by HomeSliceDude
Hello,

I've already posted this in the Cummins forum but it seems nobody there had heard anything like this before, so I though I might give it a shot here as there seems to be more people that have a Hemi paired with the G56.

My relatively new to my, 2007 Ram 2500 with about 70T miles makes a relatively loud rattling noise when in neutral, but only after it is fully warmed up. It looks like it has ATF+4 in it and is not overfilled. The fluid looks clean and doesn't smell burned, the transmission shifts smooth and the clutch operates fine. It also doesn't whine excessively when in gear, but I do have a slight whine in 5th and 6th on the highway at about 70mph, which goes away if I push the stick to the right.

It makes this rattling noise that you can here in the videos below, only when it's warmed up and with the clutch pedal out, as soon as I slightly push the clutch pedal in it stops completely. If I let the pedal out it comes right back. I can barely hear the noise in the cab only with the window open and the two videos were recorded in my garage in the same spot. The sound doesn't fit the release/throwout bearing noise descriptions or anything I found online.

Here is the video of the truck after a cold start: https://www.youtube.com/watch?v=o3w0HXNnMwU

Here is the video of the truck after its been driven for a while: https://www.youtube.com/watch?v=weaPgPSU8GI

Is it correct that the Hemi/G56 combo has a SMF instead of a DMF?

If that's the case, could this just be gear rollover?

https://www.phoenixfriction.com/t-incre ... rsion.aspx

Has anybody here heard something like this before? I'm assuming it still has the original clutch/flywheel, is this normal for these transmissions with a SMF?

Re: G56 Neutral Noise Question

Posted: Tue Sep 18, 2018 9:40 pm
by Throttle 8
I have a 2007 G56 with 50k miles. It has done the exact same thing for the last 11 years----- I stopped worrying about it about 9 years ago. lol.
It is normal.

Re: G56 Neutral Noise Question

Posted: Wed Sep 19, 2018 8:45 am
by Bill2014
That is strange how the loud clicking sound comes and goes every few seconds. It definitely doesn't behave like a throwout bearing sound because it comes and goes without engaging/disengaging the clutch... :(

Re: G56 Neutral Noise Question

Posted: Thu Sep 20, 2018 10:25 am
by Retired BLM Rig
If all you do is touch the clutch pedal slightly and it goes away, it's probably the throw out bearing rattling against the pressure plate. In the video it looks like you're applying more than a slight touch though. Probably gear rollover.

Re: G56 Neutral Noise Question

Posted: Thu Sep 20, 2018 12:36 pm
by DamageWagon
Reminds me of my dirt bike when I’m neutral and clutch out, has a constant rattle. I believe due to the gears not being engaged any drag by the oil flow causes them to click together.

This doesn’t sound like that. This sounds like a resonance coming and going. I’m with the other guys here that sounds like a throw out bearing because of how the clutch handles it. Could potentially be part of the clutch release system not having contact against the clutch.

It might make noise but if it hasn’t exploded at this point...

Re: G56 Neutral Noise Question

Posted: Thu Sep 20, 2018 4:09 pm
by Colibri
Pretty sure it’s gear rollover. A lot of g56 guys run gorilla juice and/or slightly overfill.

Re: G56 Neutral Noise Question

Posted: Thu Sep 20, 2018 5:58 pm
by RustyPW
Colibri wrote:
Thu Sep 20, 2018 4:09 pm
Pretty sure it’s gear rollover. A lot of g56 guys run gorilla juice and/or slightly overfill.
Twinsticky runs something like a 50/50 mix of ATF and gear lube. :lol:

Re: G56 Neutral Noise Question

Posted: Thu Sep 20, 2018 11:41 pm
by HomeSliceDude
Thank you for your input!

With my foot off the clutch pedal, the rattling noise is there constantly. It going away and coming back in the video is me pushing the clutch pedal and letting it out repeatedly.

It goes away completely as soon as I push the clutch pedal slightly, I just wanted to clearly show that it goes way with the clutch disengaging as most info I've found on bad bearings describes the opposite.

I found a shop in my area and the guy, unlike the other two shops that wanted to sell me a complete rebuild right of the start, wants to take the PTO covers off first and have a look inside with a camera. Just listing to the video, he thinks it might be a chipped tooth.

If he can't see anything obvious, they are going to change the fluid for now. Im thinking about going with the royal purple synchromax and then try to overfill it if the noise continues.

But, first I have to finish fixing my exhaust manifold leaks and reinstall my headers :roll:

Re: G56 Neutral Noise Question

Posted: Fri Sep 21, 2018 1:29 pm
by Colibri
http://lazarsmith.com

This is the man for any and all questions or concerns with the g56

Re: G56 Neutral Noise Question

Posted: Sun Oct 07, 2018 11:50 am
by TwinStick
My G56 does not make that noise. You can just barely hear hear my throw out bearing, & when you depress the clutch, it goes away. It sounds nothing like that though & you really have to listen hard to hear it all.
Yes, I run a 50/50 mix of Mopar ATF+4 & Lucas Lube 140w gear oil. No problems so far. Shifts 1000% better than it did when new (for those that don't know, I changed to this the day after I took delivery because the truck shifted so hard, i had to come to a complete stop to go from 1st - 2nd, 2nd -3rd & 3rd - 4th. With 186 miles on the odo.)

I drained & refilled & checked fluid again at 15k & 45k. Oil looked as clean as the day i put it in, smelled new as well. My theory: Straight ATF+4, while a high quality full synthetic fluid, is just too damn thin & completely drains off the metal when sitting overnight. Remember, I did this before there was Gorilla Juice, which is 140w oil. And, I also did this before we found out that this exact transmission is used overseas in med duty delivery trucks (like a smaller version of the UPS delivery trucks) and that Daimler Chrysler specs a TOTALLY DIFFERENT OIL FOR THE G56 THAN Dodge/FCA does. They spec Mobil Delvac 50w gear lube.

Things that make go Hmmmmm.

In the winter time, when very cold, it is hugely beneficial to put t-case in Neutral, gear shift in 4th, let out clutch for a few minutes before driving.

Your results may vary. My truck spends most of its time towing, 1/2 of its life towing at max weight of 10,500 lbs. Now it just tows 3500 lbs.

Re: G56 Neutral Noise Question

Posted: Wed Nov 07, 2018 8:15 pm
by HomeSliceDude
After changing the fluid to royal purple synchromax without any change in the neutral noise I ended up taking it to the previously mentioned transmission shop.

After taking it for a test drive and listening to the noise the guy guessed it is the release bearing.

They got it pulled apart now, the release bearing was dry and the clutch almost completely worn out. So I'm getting a new release bearing, a new clutch and they machined the flywheel which had a couple of hotspots.

I think there are two members in this forum that had their release bearing fail at about the same mileage...

Lastly, since I wasn't able to find a clear answer online, for anybody else who is wondering, yes the G56 on the hemi has a smf not a dmf.

Re: G56 Neutral Noise Question

Posted: Thu Nov 08, 2018 8:42 am
by FordyceCreekTrail
The thing I learned a long time ago is just how much more prone to issues stick shifts are. Then I took and automatic loaner off road while a new clutch was installed in my truck, and lets just say that was that. Ok, so not quite, I had a flat tire and there was no jack in the truck. But that is another story.