ripping r

[QUOTE=Quote:
Originally Posted by patdaly
CD, the SMF conversions vibrations will not affect the trans at all.

Do you have information to support this? That's really what I'm looking for.[/QUOTE]

I would like to know for a fact also. i hope i dont need a new clutch for years but you never know.

mitternocht

I installed a SB clutch with solid flywheel. It rattles at idle at stop lights when the engine is up to full temperature in neutral with no pressure on the clutch pedal. I believe this is normal.

It also causes gear train noise at low RPMs. The only time this happens is below ~1400 RPMs in the higher gears. It usually happens when going around corners in 4th or if I take it too low in 6th.

I try to say out of this “gear rattle zone”. Driving in this “gear rattle zone” is probably what wrecks the stock DMD flywheel; however you don’t know you are in this zone when stock because the stock flywheel isolates the vibes from the Trans.

I installed a fluidampr after about a year on the SB. The fluidampr does reduce the gear rattle, but it doesn’t eliminate it. I don’t know… maybe it takes away 25% of the gear rattle.

Will this wreck my trans before anything else? I don’t know; probably shortens its life, but how much? (Does it take a 500K mile trans and make it only last 400K?) I’d rather my trans not go bad, but if it does I’ll have an excuse to put in the newer G56 with the higher ratios. I doubt many will get 500K miles out of these trucks without throwing parts at them anyway.

DaveB.inVa

I look at it like this... there are thousands of other vehicles out there that do not run a dual mass flywheel and they do fine.

patdaly

That's kind of hard to prove except for the fact that billions of billions of miles in millions of Manual transmissions have been logged before Dual Mass flywheels were even invented.

If dual mass were easier on parts, wouldn't you think heavy equipment and Semis would run them?

Marketing is king...................

CORam2

I understand what you are saying...but the DMF is part of the original design of the vehicle. Now was it designed only to make it more "comfortable" for the passengers? Or was it partly engineered to relieve the high stresses seen in the transmission/t-case and other drivetrain components caused by vibrations that are specific to the design of this vehicle? Just because larger, heavier vehicles use SMFs does not mean that a smaller vehicle is capable of using it. The smaller vehicle might be designed around a DMF.

ripping r

it may have more to do with the aluminum housing the G56 uses. where the older trans used cast iron.

pind

Ultimately, just form my experience.

Dual Mass flywheels, are a more expensive, more failure prone way, to help transmit power from your crankshaft to your transmission. I see very little benefit to them, unless you like changing clutches and flywheels. In that case, they are great, because you get LOTS of practice.

A DMF will fail, 100% of the time. It is only a matter of time. A SMF will usually outlast the vehicle it is installed in, unless the clutch is abused beyond belief. And yeah, that happens.

Clutch rattle is common with double disk clutches, and it will happen whether you have a DMF or SMF in front of it, it is simply the nature of the beast.

Although the DMF does take a small part of the torsional vibration out of the drive line, in the proper operating range, where the engine spends most of its time, the benefits are negligible. The SMF will cause a bit of a rattle or "growl" lower in the rpm, as harmonics are transferred from the crank, through the clutch, and into the transmission, however, unless you spend ALL your time lugging your engine, this isn't an issue.

Down in the " rattle zone", the DMF is doing its job, damping the harmonics, but in the same process, is slowly being destroyed by the same harmonics it is meant to remove.

For the record, I would sooner go with a SMF, and a fluidamper, than a DMF any day.

On trucks that tow a lot, or haul decent loads on their decks, I normally see DMF failures within 25 - 35,000 km. No, not miles, KM. Lots of these are single driver vehicles, with stock power.

Normally, on a single driver work truck, I will see anywhere from 100 - 200k km on a SMF system, with a good clutch.

Just something to think about.

gadget.35-06

AND...make SURE you follow manufacturer's instructions when installing a SMF conversion....the knucklehead shop that did mine left a spacer on the crank, that is used ONLY with a Dual Mass flywheel, and tried multiple times to install the gearbox. I think they ruined, or at least stressed, the input shaft bearing in the process. I now have a growl from the gearbox idling in neutral with the clutch engaged...and the shop has changed hands so my warranty is kaputt. In addition, they tore the shift tower boot($103.00!) and refused to replace it despite several phone calls.

littlebigtruck

We have switched all our trucks over to SMF clutches/flywheels, and have never had a problem since. The DMF's are junk IMO and would highly recommend to switching over if you already haven't. As for that tore shift boot do you mean the orange one on top of the transmission, or the one you see inside the cab? There is a thread on here about using a CV joint boot to replace that orange boot. Those are always ripping on everybody's trucks, pretty common problem.

tonyd01

normally see DMF failures within 25 - 35,000 km. No, not miles, KM. my 06 has 97k miles hotshotting with a 36ft gooseneck and no trouble.

Totallyrad

I'm at 105k and still on the stocker. I tow 12k regularly. I priced the LUK stock replacement from Automotive Friction here in Birmingham last summer. I believe the price was around $425 plus tax. They would rebuild my stock clutch for $100, surfacing the flywheel was another $30.

gadget.35-06

Littlebig---I was talking about the orange boot, which I was able to replace with a CV boot from a Honda Insight.

Totallyrad---your year didn't use the DMF. That's why it's not dead yet.

NickBeek

Go with the solid flywheel. When you change the clutch out you will see why. My clutch was slipping at 90K miles with an added 65hp. When we changed the clutch out with a SB Con Ofe we found the clutch lining itself pretty much pristine, the DMF was slipping and the springs that do the dampening were all hosed. Most clutch disks have a sprung hub and will protect the drive line. The DMF was put in place purely to deaden the noise so customers wouldn't complain about noisy transmissions. It's just like the oil pressure gauge in our trucks. Chrysler didn't save money on components by going to a oil gauge that is really just an idiot light, but they did save on warranty claims of "low oil pressure" at idle.......

CORam2

This is all good discussion...and I appreciate all of the input. Now, to stay in-line with the original question, does anybody have ANY input on the Napa SMF conversion? Has anyone used it? Or do you know anyone that runs it? Do you think it would be similar to the other SMF units out there? Is it worth a shot?

Not sure if I want to be the guinea pig or not so I'm hoping for some input on the Napa unit.

Colo~Dirtbikers

Have 88k miles on my napa kit. I haul rvs for a living. I am empty half of the time, and weigh 20-25k the rest of the time.

No rattles and it works very smooth.

I figure maybe 30-40k more and I'll put another in. I always lose the throwout bearing before the clutch. I just do the whole thing about every 125k or so. that way I dont have any surprises out there away fom home.

Not as good as a SB, but way cheaper. Since I always lose the TO bearing first I dont see any point of an expensive clutch.

Carey