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G-56 guys, CLUTCH UPGRADE!! No more DMF!

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Gary - K7GLD said:
Wait a minute, let's sorta level the playing field a bit!



As an example, I increased the power of my 5th wheel towing '02 truck by 50%, (forseeable misue?) :) then DROVE it for about 2 years and 25,000 miles on the STOCK drivetrain,

<stuff snipped>

The BIG question is, will the G-56 allow that same level of engine upgrade, treatment and use, and still keep clutch upgrade costs anywhere NEAR the same level, for the guys who BOUGHT them for "heavy duty" use?



Owners, and prospective owners really need to know *2 things*



1. WHAT can they reliably expect in trouble-free operation from a stock, or moderately modded truck with a pure STOCK G-56 setup - and if THAT answer comes up short:



2. What alternative upgrade will be economically available to cover what DC failed to provide?



The subject of this thread will hopefully cover #2 - but the answer to #1 might take a bit longer to determine.



And for my money, a "properly" designed and operated STOCK OEM setup, including engine, working within manufacturers load and maintenance specs, SHOULD deliver well over 100,000 miles without attention to transmission or clutch.



Start bombing, and all bets are off. .
.



I think that is the key takeaway. It is easy to expect same or better performance than the preceding model widget. It is also OEM credo to make the same (or whatever spec level) performance with less cost. Naturally, a consumer will enhance performance, it is a "forseeable misuse" that the OEM needs to be cognizant of but will add language to minimize its own risk at the consumer's expense. Replacement clutch costs or upgrade costs are not really considered as we buy $40K trucks and are expected to do whatever it takes to follow the service guidelines.



It's gonna be a long month to wait for first cut results on this stuff.



YMMV
 
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This thread is a win-win proposition for a few who want to see how much they can stir up. No matter how it turns out they can continue to say you guys bought junk. If SBC comes with a suitable replacement for the DMF, then you guys bought junk. If SBC says, in their opinion, the transmission won’t take 600 HP and 1000 ftlbs of torque, then you guys bought junk. Those of us that have an interest in the way this comes out, we will find out, but however not without a lot of needless belittling, harassment and derogatory dialog.



It’s too bad this has to be this way, but that is the way life is. You pay your money, you take your chances and you live with it and you get over it or not. The last time I looked there were over 25,000 people that paid $35 to use this forum and from what I can see most of them haven’t posted yet. I would bet that after viewing what they paid for, a lot of them won’t post because of the fear of being badgered and belittled.



I like a little teasing and having some fun as much as anyone, but some of these threads go just a little bit too far. The moderators do a pretty good job at keeping thing in hand. There is supposed to be a three strike rule here but luckly it isn’t enforced. If you want true free speech, start your own blog and have at it.



If and when ( and I expect it to ) my clutch fails I will not report a thing about it on this forum. That’s too bad because we all need to learn from failures.



Dave
 
Dave -- I honestly don't understand where you're coming from. This board is MILD by comparison to some of the debates that are found on other boards. Personally, I don't tease other people -- I do tease about my G56. As a G56 owner, I just don't see all the bashing that you're referring to. If someone says that I bought junk, they may be right. But it doesn't bother me one bit. My M3 / 540iL friends think I'm crazy for having a truck in the first place. The truth is the class of 2005. 5 are the G56 test subjects. That's a fact. I'm not happy about it and I guess I blow off steam by teasing my own truck -- i. e. plastic gears, etc... I don't see a problem with it.
 
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scotty1 said:
After reading through the thread I found that a few folks had an opinion well formed about the guy that was involved with this test for 'other' reasons. I am not aware of what happened and don't care.



I do want to know how this pans out as my neighbor has a G56. Speculation, preconceived ideas and misinformation is the stuff I try to steer away from. When I do not have the knowledge and experience like some people have, like Peter; I wait for him to post factual feedback on a totally new horizon with these trucks. Some of us say look past the stuff you don't want to read... well I guess that applies to all of us... whether or not its about humor, belittling, babble, facts or topics that are not of interest to us. ;) Scroll on.



Scotty



Experience,

The key to understanding the TDR! I too would love to see some kind of answer about the G-56 transmission. I have one waiting to be delivered. It will be here in 11 days and I am sure it will be bombed, built, bashed, and rebuilt. Having a solid clutch is key. Having a rock solid trans is another. Maybe we will be having the Manual Trans bombed like the auto guys do. That wouldn't be so bad either.



Greg
 
Maybe we won't even need to mod the trans. Maybe all that is necessary is a clutch upgrade. I will know one way or another after this is over with, for sure.
 
Dual Mess

As a side note:



Last week we had one of the two Chebby DMax 6speeds in the shop. At idle it shook like a gasser with several plugs removed. They replaced the DM clutch, p plate, and flywheel. Luckily it had 35K on it. This is two out of two DMaxes that have had the DM clutch replaced under warranty. They are used to haul 8 horse trailers and a gooseneck flatbed.
 
I like the concept of Dual-Mass. Smooth power, no vibration, low stresses, long transmission life, no need for springs in the center of the clutch disc (which makes it easier on the synchros having less rotating mass). The extra mass of the flywheel is attached to the engine, not the clutch disk, so when you depress it, the synchros don't deal with it.



But not if you have to replace 3 or 4 flywheels to save one transmission. And when they fail, they can probably take the transmission with it too.



The right way to do it is to make the D/M flywheel last one million miles of towing.

It can be done, and may cost a few bucks more and weigh a couple pounds more.

Until then, I'll keep my nv5600.
 
Hey SBC if you need a extra test dummy I have one. Its a 2005 3500 G56 Quad Cab Sport Laramie. I have done some mods and I have been begging my local preformance diesel shop to do a clutch swap. (There Scared). It has a crazy larry an edge with attiude stacked,fass 150,bully dog 5",afe stage 2,ats arc-flow intake,and mt baja claws 33/12. 5/17. You can keep it as long as you want and I dont even need a loner truck. I have been driving it for 5000 hard miles with these mods and my plastic gears have not melted yet.
 
South Bend Clutch said:
I do!!!



Folks, the DMF is not new by all means. This has been used in Europe for many many years. The 1987 6. 9 and 7. 3 Ford trucks were introduced with the Valeo drive train to the US and for the most part, when failure did occur, it was due to a couple of reasons, overloading the truck, bad engine performance i. e. bad injectors, etc. Also, the original design carried an 11" clutch so Valeo made a replacement unit flywheel/clutch, to move it to an 11 7/8". In 1994 they came out with the PowerStroke and made a heavier duty flywheel that supported a 12 1/4" clutch. Again, I saw many of these trucks get lots of miles out of the flywheel and clutch unless there was engine problems or too heavy of work loads. In 1999, when Ford went to the 6 speed, they went to a solid flywheel and tried to build a heavy duty spring loaded disc. This failed miserably. The disc springs broke out in short periods of time, especially with them heavy haulers. In 2003 Ford made the 6. 0 diesel and went back to the dual mass flywheel for the F250s and 350s and offered a solid flywheel system for some of the 350s, 450s & 550s. From day 1 none of the clutch systems could handle horse power or torque inhancements. This is obvious, the manufacturer builds to clutch system to handle the stock power. Now Luk came along and designed a solid flywheel replacement package for the Ford industry. This happened in the late 1990s. The units worked fine but would exhibit some drivetrain noise due to the lake of the dampening dmf. Did the transmissions start failing? No they didn't. But the clutch systems would not hold more then 300 hp, that's where we came in. The clutch for the Ford that Luk designed is actually a replica of the system Dodge uses with the 5. 9 Cummins. The Chevy 6. 5 in the early 1990s supported the Valeo designed clutch and flywheel. Again, it was fine for stock applications but any engine problems, enhancements to the torque, or overloading caused premature failure. Luk became very powerful in the industry with their solid conversions and got the OEM for the 6. 5 Chevy. The solid flywheel and clutch packaged designed for the 6. 5 failed miserably. The spring loaded clutch disc fell apart in short time. We converted many trucks back to the dmf. Luk then, in the mid 2000s, got the OEM for the Ford 6. 0, the Chevy Duramax and remained the OEM for the Dodge Cummins. Now, here's the company famous for the solid flywheel conversion now desided to put dmf in all of it's trucks. Most of the Duramax dmf fail within 30-40,000 miles and they have been scrambling to revamp the dmf. The Ford 6. 0s, same thing, put any horse power to the truck and she's toast. Now the Dodge. Folks, this transmission was used in Europe with the mid-sized Mercedes Benz trucks in the mid '90s as a test unit. It could not stand up and was dropped. They decided to bring the transmission (G56) back to market in the smaller truck i. e. Dodge Turbo Cummins Diesels. I believe their thinking was, smaller truck, less stress. The OEM manufacturers could care less about engine enhancements. The system is built for the power offered by the truck. In my opinion, if you leave the truck stock, keep it tuned, don't overload it, the system should last a good long time for you. There are also many passenger cars today being built with the dmf, Corvettes, Porshes, VWs, even Hyundai Tiberons, and many more. Again, everything works fine when the vehicle remains stock, once the horse power and torque is amplified many of them start to fail.



Back to the main topic, (please Tim, don't take this wrong) but I am not counting on or asking Tim to be a person to report back to the TDR forums with the results from ourselves and Blumenthals. I, along with Blumenthals, will together report our findings. There will also be an up and coming article in the TDR magazine. Folks, it was not like I had a dozen people offering their trucks for this type of work for me to chose from, I have thrown many leads out to see if someone would step up to the plate. Tim was the only one. Therefore, if and when something is designed, of course, it will be free to him. However, I am not about to automatically slap a solid system in his truck and wait to see what happens. This is the reason for doing the work at Blumenthals. I will have the experts in the transmission field, along with myself, going through the transmission to see if it will support such actions. I want to stress very loudly here, STOP THE BICKERING. If you leave your truck alone, for the time being, the system WILL perform fine. Our goal is to find out how far it can be pushed and what can be done to improve, if needed. Think about it. None of the transmissions, automatic or manual, dealing with torque converter or clutch, has been able to handle torque enhancements to a degree. What makes anyone think this setup will? It won't. Possibly mild enhancements but nothing major. I am not only doing this for you, or for us, but also for the companies that build the power modifications.



I hope this helps, and again, I will personally report back mid September.



Peter

Thank you SBC for this extensive history... However, I thought it was time to "clear the air" on the whole DMF/G56 debate:

1. ) The DMF was requested by DCX, not "decided" by LuK

2. ) The DMF is not responsible for the added drivetrain lash. Extensive testing has been done to verify that tip-in/back-out lash is linked directly to trans/transfer case/propshaft/axle windup, not DMF slop.

3. ) The DMF does an excellent job of isolating engine fluctuations from reaching the transmission. For you math gurus out there who understand this stuff - the engine produces upwards of 150 rpm peak to peak fluctuations per firing, while the transmission only sees 10-20 rpm peak to peak thanks to the DMF - that's got to be worth something to the transmission's durability.

4. ) The famous DMF which gave the bad name, the Ford Valeo DMF, is an entirely different design and not produced by LuK! Yes, Luk Aftermarket stepped in and replaced it with a solid mass because they couldn't fix the Valeo design to make it durable (bad design from the start).

5. ) The 5. 9L DMF is produced in the good ol USA, not Brazil.

6. ) You can thank the LuK DMF/Disc/Clutch design for that low pedal effort and smooth engagement - beacoup bucks were spent to develop it into a nice package.

7. ) And on the topic of R&D, LuK purchased multiple vehicles for the development of this package, as well as evaluating 30+ vehicles supplied by Chrysler. Some of the LuK-owned vehicles now have over 200k miles on them now - do you really trust a product from a manufacturer who can't even purchase one vehicle?

8. ) And by the way, for those of you who have heard that the DMF causes long crank times... I personally conducted the DOE on this complaint and found the DMF to have no effect on crank/cam sync time. It was theoried that it could have an effect, and I regret that the rumor was passed on to the dealerships in that manner.



Hopefully this doesn't start a flame war, but I thought it could be beneficial to hear the comments from somebody who knows this product... very well.



Red_Smoke

"Dabbling in powertrain NVH, every day of the week"
 
Red smoke, can you tell us what kind of service life to expect out of the DMF?

How much power can the stock clutch and DMF take before damage occurs?

Do you have suggested solution for the extra driveline lash? Is it even a problem?



Thanks,

Jay
 
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