Danderson

Staying with the NV5600 would have negated all this nonsense. Daimler wanted to sell more of their transmissions,hence the G-56's.
I drove a friend's NV5600 yesterday and despite slower shifting/downshifting due to the DD,it's silent putting through parking lots. No growl. Sloppier shift pattern also. These G-56's do have very concise shift gates.
My friend and I bought our similarly equipped '07 5.9 G-56's at the same time. His truck weighs 10,570# and runs 285-75-17 tires and a flatbed mounted Phoenix popup. The guy's got 60K on it,stock power and has accumulated thousands of miles in Baja including deep sand aired down for miles in lower gears. Stock clutch. No slip to date.
Mine never did slip either even with my constant camper load and Smarty sw#3,stock torque management. Neither of us tow.
The 0.79 final drive of these early g-56's mimics 4.10's on an auto. This must help save the clutch.

Jona Gold

Everybody has a different need from their truck, and we're just lucky enough to have plenty of options from stock to crazy modified with these Rams.

I saw info on swapping to the older 6 speed while doing research, but it was more effort and cost than I was willing to put forth.

StealthDiesel

My NV5600 is far from perfect but it was dead quiet until I installed an aftermarket clutch.
There's always a compromise when you up the power.
My '89 5.0 Mustang also has an aftermarket clutch and it requires way more leg to push it to the the floor than the SB DD3250 in my truck.

If I had a G56 with my current power level, I think I would go for the latest Southbend DD3250 but would ask Southbend to build it with more damping springs in the sprung hub instead of the urethane "pucks" to reduce gear rollover.
But the softer sprung hub would likely not be recommended with an exhaust brake... more compromises...

zfmax

Man, can I relate to a lot of what's been said here!

I've been down the path with SMF's on my Duraheap. Noise, vibration, and clutches that didn't last any longer than stock. Often less. Accused by a major clutch vendor of not knowing how to drive my truck because his products repeatedly failed on me. Told me I can't tow in 6th gear after I had spent thousands with him and had two early failures. Had another brand disc on an SMF literally disintegrate from the vibration. Lining was great but the rivets all came apart.

When I bought my 4th Gen Cummins with it's factory DMF, I immediately remembered how smooth and quiet these trucks are supposed to be.

I would MUCH rather have smooth and quiet and deal with a periodic replacement than have noisy and rough and deal with periodic replacement - and possibly tranny damage to boot.

There's a reason they put DMF's in these trucks. The aftermarket needs to get their act together and come out with improved DMF's and clutches for them, not push all this SMF garbage on us that vibrates and makes noise and tears up the transmission. Just my opinion.

Danderson

I've posted before that in '08 I suggested LuK build us a 60+ hp dmf for this aluminum cased trans. The contact person was going to refer the idea to marketing and engineering. Still waiting.

Jona Gold

Last two tanks of gas have been right around 19.5mpg hand calculated- the best I ever had with the SMF installed was 18. My commute is 45 miles of 55mph country two-lane with a couple little towns I slow down to 30 for (no stops). I need to have my speedometer re-calibrated though, because I'm running 2" taller tires now- so it's actually a bit better than that as I'm traveling faster/farther than the speedometer/odometer is reading (new tires came after reverting to DMF).

Words can no longer express just how much happier I am with my truck, it's drive-ability, performance, and fuel efficiency. The DMF is where it's at for this guy.

zfmax

Me too. People think I'm crazy. But they didn't go through what I went through with SMF's and clutches in my Duraheap.

truckmen

Hello all,

I know this thread is over 3 years old but this is what I found while trying to remedy my problem putting in a SBC 3250.

I'm almost finished with the install taking more time than I will admit to here on the forum. I just hope, after days of hell doing this myself, that the result won't be regretted.

The reason this grabbed my interest is it's the first I heard of the regrets by others going aftermarket Solid mass flywheel (SMF).

I have 194,000 miles on the original equipment, a '14 3500 with the 6.7/G56 setup. Of those 194,000 miles, at least 150,000 miles are put on this truck hauling a 4-car Wally-Mo grossing between 30,000 and 38,000lbs. Only recently I am having problems with the truck jumping out of high gear while coasting down grades with engine brake on.

But is was my throw-out bearing that gave out completely and by the time I limped back home the throwout bearing was completely destroyed taking the fingers off the pressure plate in the process. So, when got ready to change everything out, I'd opted for the South Bend clutch kit: SDD-3250-GK-ORG. As most everyone knows by now, this is the 3250 dual disk, single mass flywheel (SMF) and associated hydraulics. Along with this kit, I also upgraded the input shaft bearing retainer with a cast iron version and threw in a new pivot ball.

I hope I can come back here and say I am lucky (again) with this setup. I still intend to haul heavy loads throughout the 48 states.

Any comments or remarks are gladly accepted.

Ralph

Jona Gold

I've been away a long while, but I still own my Ram, and after 6 years and 60K miles I'm happy to report that the OEM style Luk clutch I installed and did this write up about is still working flawlessly. I still have the Edge on the truck, and use the towing setting (2), and ever so often the "Drive" setting on 3, but unloaded use the first setting for MPG. All three settings add power.

I still love the smooth, quiet power of the dual mass and it has already proved to be far more reliable than the aftermarket options I tried. Eventually this clutch will give out, given it's a consumable part. When it does I'll update as to how many miles I got. I bought my truck new and got 105K out of the first clutch. I expect I'll get that out of this clutch.

Danderson

A friend of mine with the same '07 as mine has 80K on his original LUK. It's got an aluminum flatbed and a 1600# popup on it. He tows occasionally locally and has thousands of 30psi aired down offroad miles in Baja. Miles and miles through silt and sand. The clutch has been flawless. I got talked out of my stock clutch at 37K by a trans installer I went to for a seeping rear main. I miss that stock clutch. I had a 60 rwhp Smarty tune on it the whole time and a 2200# popup too. 285-75-17 tires.The stocker was like new and I sold it for $100 to another 3rd gen owner.

Connotaucarius

Reviving an old thread again. I replaced the stock clutch at 99,000 miles. It had a good life but, started to slip when I accelerated hard in top gear, at low RPM. So, I installed the Southbend DD 3250 with new hydraulics and ETC... It worked well but, wasn't totally happy with it. The 3250 was more grabby at the low end, and caused the tranny to rattle until the engine RPM exceeded maybe 1600 RPM.

The stock clutch seemed to hold Smarty level 7 in top gear as long I was turning over maybe 1800 RPM before standing on the throttle. The DD 3250 allowed me to stand on it at lower RPM however, the transmission rattle below 1600 RPM always prevented me from running at that speed. Since the stock clutch allowed me to idle down to almost idle if I needed too, I never realized the true benefit of the Southbend.

Coming back across the rockies last week, towing a 6,000 trailer, the clutch started act up on me. The clutch pedal started feeling progressively more and more stiff. At times, it even felt as though the throughout bearing was sticking a little. 2 days later during the same trip, after driving through Los Angeles traffic and driving 2200 miles, I was about 20 miles from home, the clutch slave cylinder let lose. So there I was, driving through Ventura CA traffic with no clutch. I was able to speed shift, a real challenge in stop and go traffic with a G56 but, having a very low 1st gear really helped. I eventually made it into a parking lot. Yes, all while still pulling a trailer.

While waiting to be rescued, I pulled out the slave cylinder and was shocked what I saw. The rod was fully extended (not surprised based on the brake fluid loss). But, I was surprised that the rod was bent and had very clearly been grinding on something.

The truck has 134,000 miles on it, the stock clutch lasted a relatively problem free to 99,000 miles, and the Southbend DD 3250 choked after maybe 35,000 miles of being installed. I want reliability and something that allows me to idle down in gear if I want to. I'm going back to a stock clutch. Probably to a Luk 05-182.

About the truck, I typically run it on Smarty level 7, cat delete, AFE air filter and a PacBrake PRXB. While towing, I dial down the Smarty to level 3 and will downshift if my EGT's begin to exceed 800 degrees (Pyro is post turbo). I don't drag race, I don't sled pull, it's just a daily driver, tow vehicle. And before you comment about the Smarty level, I really only use the power available when I'm on the freeway and need to dodge ricers. ;-)

Jeff in TD

I’m kind of interested in this topic as well. I have an 06 with almost 100k on it, stock power and will remain so, mainly used for towing.

Stock clutch doesn’t slip, but the throw out bearing is beginning to make noise when you first take slack out of the pedal. Satisfied with the feel and life of stock type dmf.

Wondering about Napa’s kit- dmf flywheel, clutch, throw out bearing deal.

Mexstan

Recently I replaced the clutch on my truck with a Valair single disc. So far I am happy with it, although it does rattle a bit in neutral and sometimes while accelerating. Valair did tell me before I installed it that this was possible but normal. Apparently adding an extra quart of oil in the tranni quietens the noise, but have not done that as I will soon be changing the tranni oil and will do that at that time.