UPGRADE: 6.7 harmonic damper on 5.9

[JBlakeman]

5.9 vs. Fluidampr vs. 6.7?

I have to replace the seal on my front crankcase due to a new oil leak right above the A/C compressor. Since pretty much everything has to come off to replace the seal it would be a good time perform this upgrade to my still factory setup at 186k.



I know the NVH is way better with the 6. 7 damper installed however I'm wondering if anyone has already replaced their 5. 9 damper with another 5. 9 damper and 'then" found the new 6. 7 damper to be better especially given as these engines age they get louder anyway from valve train noise anyway?



I was pretty much sold last year by Fluidampr's presentation of their replacement for the 5. 9 at the Diesel Extravaganza and the fact that they claim "it'll be the last damper you'll purchase... ".



So going from "original" to Fluidampr will I still see the same benefits that everyone else is getting from the 6. 7 that will still be a "replacement" item or spend the extra cash for a Fluidampr that will be a onetime replacement?



Thoughts?



Jon

 

[George Cameron]

The 6. 7 damper is viscous like the fluidampr and is a one-time replacement vs. the rubber mounted inertia ring damper on the 5. 9 that can be a recurring failure point.

 

[Prairie Dog]

The fluid Damper works far better than the 6. 7 does at reducing NVH. There really is no comparison as far as I'm concerned and I would still be running one if there wasn't the noise issue. But, the 6. 7 was also a marked improvement over the perfectly good 5. 9 balancer I took off my engine that only had 75K miles on it - especially when it comes to manual trans operation.
If you don't mind the chattering noise of the FD and the fact that it has to be removed to change the belt, it will pretty much rid your truck of exhaust drone and greatly reduce trans/clutch noise.

 

[JBlakeman]

Great info... . so would you go with the Fluidampr (considering it's increased cost) or do you think the 6. 7 damper would be sufficiently as reliable. Just not sure from a labor / longevity standpoint which is the more practical solution??

 

[Prairie Dog]

The FD is worth while IMO if you have a manual and if you can put up with the clattering that some trucks have with it - like mine. With an auto I think the 6. 7 would be just as good with the exception of killing the drone. Frankly, with an auto trans I'm not sure you would be able to tell any difference between a 6. 7 and the HB you have now. I don't have any experience with that configuration.

 

[GSchroder]

Ordered my 6. 7 damper today (4933224@$233. 95) and associated parts from the local Cummins dealer. BUT, everything except the fanpulley is coming from Germany. It'll be a month or so till delivery. I will post my impressions of it using an auto transmission. Prairie Dog, I am the guy that picked up the chrome wheels you had for the guy in CA.

 

[GSchroder]

Just noticed my truck info is outdated

 

[Prairie Dog]

Ordered my 6. 7 damper today (4933224@$233. 95) and associated parts from the local Cummins dealer. BUT, everything except the fanpulley is coming from Germany. It'll be a month or so till delivery. I will post my impressions of it using an auto transmission. Prairie Dog, I am the guy that picked up the chrome wheels you had for the guy in CA.

Oh ya! Recycling at its best.
I'm looking forward to hearing your observations with the auto.

 

[JBlakeman]

Well an update... my leak originated from the water pump as it finally gave way to a full stream under the truck on Tuesday. Front cover is still sealed tight so therefore don't necessarily need to change the damper yet... Note this is my 3rd water pump since new... .



Interesting enough I asked the diesel shop who did the work whether they run into these dampers being replaced on the 5. 9 HPCR engines and surprisingly they feel it's not needed unless you plan on adding tremendous horsepower (their baseline is anything over 500 HP). The older engines seem to have more "issues" with damper isolation due to more vibration (and front cover / dowel pin concerns) therefore they see more dampers being replaced on 12V and 24V engines and even then most are replacing them with stock units.



Considering maintenance being foremost and being able to service the belt whenever necessary without having to deal with the damper, I'm still considering the 6. 7 damper. Does this damper really "quiet" the engine down or is it still that classic 5. 9 sound just smoother drive-ability and less vibration?

 

[Dieselnerd]

I've already had belt change issues with my Fluidampr, and had to change my belt twice on the road. Not fun!



Now that my Fluidampr is sitting on my workbench because of the "noise", I won't be putting it back even if they solve the noise problem. Why? Change a belt in the rain on the road and you'll know why...



It did smooth the idle (while adding a tinking noise) but on my stock truck it wasn't a big change when driving.



I have my Fluidampr for sale (cheap) in the classifieds but I think the noise issue, which I disclose, scares buyers. You won't know until you install it whether or not your truck will have the noise.

 

[Prairie Dog]

Now that Cummins has done half the work for them and designed the new fan pulley, FD needs to step up and design a balancer that allows belt changes with the new part.

 

[Dieselnerd]

Be nice if they removed whatever part of the design causes the noise too!#@$%!



I don't understand why the Dodge Fluid Damper doesn't make a noise while the Fluidampr does. Aren't they basically the same thing internally?

 

[Prairie Dog]

The Cummins part is shaped a lot different (narrower but bigger in dia. ) and it's my guess that it is highly tuned for specific parameters but the FD has a much wider range of effectiveness. Perhaps the better tuning ability of the FD would be compromised if the body was altered. I sure wish they'd try though.
I think it speaks badly for FD that they haven't provided any more info on their problem.

 

[JBlakeman]

Great info and I definitely don't want to be stuck messing around with a belt out on the road... . and sounds like the additional "noise" isn't worth the 2x cost of the FD damper vs. the 6. 7.



Going ahead and ordering the 6. 7 with the fan pulley on Monday...



Any great sources to get these parts from or should I just go through a Cummins dealer?? Also would I need to provide a serial number or anything like that (since I have a 5. 9) or do I just have to provide the above info... .

 

[AH64ID]

The part numbers is all you will need. I just called my local Cummins shop.

 

[MAshley]

So how is everyone enjoying or. . not enjoying thier dapener change to a 6. 7?

 

[AH64ID]

I am enjoying mine!

 

[Prairie Dog]

It's working good. A bit less drone and smoother at mid range RPM's. Clutch/trans noise is also diminished. Every day I make a stop at a small shopping mall and as I turn in, I drop it into third and just let the engine loaf along. With the stock HB I got significantly more clutch/trans noise. I would say about 60% of the noise is gone whereas with the FD, it was about 90-95% better.

Updating my SmJr. to the new 514B SW improved low speed smoothness and drive-ability too.

 

[blacksheepdiesel]

Still lovin' the damper in my '04. 5 with NV5600. The '06 with automatic the damper made no discernible difference.

Godspeed,
Trent

 

[Eliminator]

Still waiting for the parts it's been over a month now. Suppose to be in next week!!!