You either have the nv5600 or the g56. You can find out by looking underneath the truck. The nv5600 has a cast iron bell housing and construction, while the g56 is cast aluminum. The nv5600 reverse is to the right and up.

 

I worked at DCX for several years before going to GM Powertrain. I was the design release engineer for the clutch hydrualics. The system for the 05 and on G56 was my baby from inseption with development starting in 2002. Going from the NV5600 to G56 system, the master cylinder (M/S) and slave cylinder (S/C) changed diameters to account for a different hydraulic ratio required for the dual mass damper flywheel (DMDF) and self adjusting clutch (SAC).

The system you speak of isn't really an upgrade but a replacment to correctly interface with the aftermarket clutch.

Here's an interesting tidbit. Prior to 2005, on development and durability vehicles, they'd typically have to replace several clutches because the disks would wear out 2/3 or so through the testing period. Over the entire cycle of the testing of the G56 up to laucnh, they NEVER wore any clutches out. Not one. The pure beauty of the SAC. At stock levels, it'll last you 150K or more. So, just keep that in mind when you bash the SAC/DMDF setup.

You can all also thank me for the awsome modulation of the clutch hydraulics. We went through many iterations and developmemt to acheive the launchability the system has now, which is as good or better than the 04MY and prior. (as in fully loaded, on a grade, launching off throttle) That system IS the benchmark.

 

I respect your background on the topic, but I have to disagree on the above point.

I installed the "upgrade" hydraulics when installing an after market clutch, it is very much different than, and appears beefier when compared to the stocker. It is marketed as an "upgrade" in response to customer complaints about failures when the stock unit is used with heavier plate loads.

 

So what was the real reason for the DMDF? Was it for creature comfort or was it to save the transmission/drivetrain from diesel pulses?

 

Gear train rattle. Anyone with an 04 and older truck that has lugged the motor at idle, can attest to this. It's very easy to induce and was deemed non commercial by managment. Chevy and Ford still do it.

It's caused by the harmonics of the engine and reached a pinnacle on the 04.5 trucks when they stepped up to the 600ft-lb package. Given the lighter mass of the G56, it was further amplified. It's also the reason you can get a "buzz" in the pedals and steering column on some trucks.

 

I haven't seen the aftermarket setup you speak about, but can understand why it could appear to look beefier. They'd have to change hydraulic ratios, M/C and S/C diameters, to acheive correct output. For instance, the 04.5 and older OEM systems are not compatible with the 05 and newer clutch. It will over stroke the clutch due to the increased S/C travel. I wouldn't be suprised if they were selling pre 05 OEM systems. Does the system say Associated Products or FTE on the body of the M/C? FTE bought AP out in 2004. Up to the point I left, they hadn't updated the tooling with FTE stamping. Although, it's been a while since I looked under the hood of the 07-08 trucks. FTE was gunning to phase out the AP products and bring in the FTE designs. IMO was a mistake if they did. They tried that with the new wrangler going down in flames.

 

A member here linked me to the SBC site and nearest I can tell, it's an OEM 05 Dodge Dakota clutch line. Take a look at this old graphic I still have. The line from the quick coupler to the S/C was nylon right up to launch. At the last minute the plant had issues with assembly and a chassis clip. A friend that took over my stuff, had to change the line to PTFE, like a viper.

Edit: Actually, looking again, the M/C looks like a Viper unit, so they must have changed that too at the last minute for the Dakota. I'll have to ask my buddy. Those are OEM part # stickers on the two pieces. It's an OEM part. It'll have AP stamped on it.

 

Found this when I was digging through stuff. Death Valley 2004.

 

Thanks for the technical info. I love my stock clutch and hope it can continue to handle my load and Smarty SW # 1. Smarty makes these trucks so much more fun to drive. It's great to hear from a product engineer.

 

I just got off the phone with SBC and they told me it sounds like the hydraulic unit. They said that the stock unit uses plastic lines and an aftermarket one uses braided stainless.

 

That, to me, doesn't make sense. Your pedal reserve (brief- distance from when the pedal disengages to the end of the pedal stroke, roughly 1.25 inches. ) shouldn't change, especially on the diesel. A hemi could due to heat. The gas engine truck have a heat shield on the drivers side. Given the exhaust is on the pass side, there is no heat, other than the trans to warm the thing up. Death Valley in 120+ degree heat was nothing and showed no degradation.

The "aftermarket" system you speak of is actually a current Dodge OEM part. The PTFE line is only used in very high temp or high abrasion situations. Viper and 2005-on Dakota. Given lack of heat, the PTFE isn't buying you anything in regards to reserve. It's a high temp plastic line with a stainless sheath over it.

IF you were losing reserve, it'd be hard to shift. The clutch getting hard to actuate, would have to be the clutch. The only part in the system that exerts a resistive force is the clutch. If you broke something in the hydraulics, it'd be leaking........ like a cracked piston.

 

No leaks. Level of fluid hasn't changed.

 

morpheus, I don't see why there aren't advantages to the (now, quote un-quote) Upgraded hydraulic unit. I mean, isn't that why we do stainless braided brake lines too?

 

I guess I could just really squash this topic by calling Peter and asking him point blank. I'm highly doubting that he would be selling a different set up just to make a few bucks, considering the massive (dollar) amount of business they do in clutches alone.

 

Stainless brake lines are for conditions with heavy braking, equating to high line pressure, in combination with heat due to the heavy continual braking. The PTFE will have a higher expansion/burst pressure than standard rubber lines or in the instance we are discussing....... the clutch line.

Sure, given a choice between two systems that are exactly the same with the exception of the line, I'd take the PTFE. But, in this case, I'll bet the change in the system is to change ratios, accomidating the different clutch. Look at SBC site. The parts they show, are OEM. See the white sticker on them? It's got a pentastar on it and a DCX part number. Also note, the entire line is not PTFE. Only the lower portion, still leaving the upper section in the standard nylon.

Something else I thought of if memory serves me right. The 05 system had a larger diameter, thicker wall nylon tubing over the pre-04 system. Likely, thicker than the replacement system they are selling. If someone would get the part #'s off the stickers, I could tell you what they are off of. And some info on tubing thickness and ratios.

Also, if someone is so inclined, ask SBC what the load is at the TOB and I can talk to the engineer at FTE (the company that makes them) and find out how much reserve is lost from the higher load.