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If shift quality or NVH is an issue, one logically would not go to a dual disk.
Not trying to be obstinate here, but the 2 types are from polar opposites of the spectrum.
If you need the most holding power with the added ability to slip the clutch some and not kill it, DD is the only way to go, you will though, absolutely not be able to shift it like a stocker, nor will it ever be as quiet as stock.
As for the LUK site, well DUH. The difference though in synchronizer wear between the two is so infinitesimal that I doubt it can be reliably measured, unless you are ham handing the thing.
I will add the caveat that I have never had a G56, nor had one apart, but I will say that if Mercedes built a trans that is that particular, then they really should never ever speak of "German Engineering".
Drive one with ATF and a smf. Dodge would not have sold one truck with a G-56 and a smf stock. The aluminum case vs the iron one on the NV5600 makes a heck of a difference.
The Delvac 50 fluid approximates the Mercedes recommended fluid and helps suppress the racket somewhat.
Some G-56's are quieter than others.
The NV5600's when badly lugged approximate the sound ours make putting down the neighborhood in proper rpm and not lugging. Not good to the ears
Diesel Junkie not sure why you have not gotten a call back as we are usually very good about that. Not saying this is your case but quite often we call customers back and either their voice mailbox has not been set up yet or their mailbox is full and will not receive any new messages. Then they call back and say we never called them back. I make all of the phone techs write everything down so I can follow up to make sure they are doing their job properly. Feel free to call me personally and I will try to help out with your shifting problems.
For the benefit of anyone following my saga, I have been focusing on trouble shooting as I drive:
1: Hydraulics are not adjustable,(outside the bell housing at least). The master cylinder bottoms out internally.
2: Noticed that it does seem to shift better when it's cold. (Should I add a cooler to the tranny?) (would a different fluid help? Is Delvac 50 the hot ticket?, amsoil 75wt was not)
3: I think my problem is the worst when the tranny is stinkin hot.(many Thousands of pounds of load)
4: Waiting for the mass to spin down does seem to help somewhat, but not the whole solution.
The Clutch Master Cylinder Reservoir is mounted pretty high above the cylinder.
See the pic below.
Peter,
I will try calling you again tomorrow. Been busy and the time zone shift kills me. Thanks for calling me back though.
Been paying close attention to the causes and effects since posting this.
Been making sure I have the clutch pedal all the way bottomed out when shifting.
Waiting helps, but does not solve it. (for the disks to spool down). I have been waiting a FULL 5 seconds with the clutch pedal down when at a stop before I pull it into second gear. Lighter pull, but still heavier than I would say it should be.
Also been focusing on Wheel speed matching while shifting at speed. If i get the engine speed matched to the wheel speed for the gear I am going to, it goes in perfectly smooth. (usually using the double clutch trick). But to make it go smooth I have the hit the window super close, like closer that 100-150 rpm off of nominal target.
Thinking of trying a few things:
1. That Delvac 50 oil
2. adding an oil cooler of some kind.
3. Changing the hydraulic fluid(in case it has moisture in it). Rather than flush it, I will probably just draing and re-fill the reservoir a few times
The reason I asked is that we have seen where people zip tie the reservoir to the power steering lines which get very hot and messes with the fluid in the hydraulic system.
Been watching this thread closely Diesel Junkie. Thanks for the details and keeping us posted. Every once in a while my clutch makes some odd noises and is a huge pain to get into reverse. Let us know how the fluid changes work out.
This weekend I replaced the clutch hydraulic fluid, and removed the spacer under the slave cylinder mount.
(Did them at the same time, so I am not sure what the individual contributions were).
(I purged the fluid by sucking the reservoir dry, filling with fresh fluid, and pumping the pedal 50 times, and repeated that 3 times. Not a full flush but not bad). (There are no bleed screws on this system).
Results:
Performance got a little bit better. definitely not solved, but a marginal noticeable improvement. Better cold, and better hot too.
I refined my testing of the problem a bit:
I noticed that in low (first) gear, I could get engagement with the pedal closer to the floor. (Normally when sliding the power on from a stop in 2nd, the engagement point feels about 1/2 way up.
So i did this: Found a really flat street, put the T-case in low range, and did some slow starts in 1st gear. When doing this, i noticed that the engagement starts about 0.5" from the floor(just barely). That is the release point where you can barely get the truck to start moving.
Then i found a very slight incline, one where there is just barely enough incline for the truck to roll back. Put the truck in 1st gear(low range) clutch all the way down. I found that in first with the clutch down, the drag could hold the truck on the incline, and with the tranny in neutral(clutch still down) the truck could roll back. (Keep in mind the effect described above is very slight).
All of that really tells me that the problem is dragging.
Now that I am more sure the problem is dragging, I was able to refine my driving style. In the past, I could get an easy shift by double clutching and matching wheel speed.... now I have realized that (If I am up shifting) I can just pull the stick into gear right at the point that the wheel speed matches, (Because the drag matches wheel speed, and inertia does not really matter).
SOOO,
All this means that I think I need a way of increasing the throw of the slave cylinder. A little more displacement should allow the disks to loosen up... I hope. The only reason that might not work is if the intermediate plate between the disks is sticky and not allowing the disk closer to the engine to release.
In the mean time, I have 4 gallons of Delvac 50 sitting in the garage ready to swap.
