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My Fluidamper saga.

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48RE shifting problems "start in 2nd"?

Code PO868 Sluggish transmission

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Someone else will have to do this test since mines a manual and I don't have the FD in anymore. I can tell you this, when I pulled the TT over the mountain at about 2000+ RPM's last year in 5th, it was so quiet in the cab that I forgot to shift into 6th at one point. There was no drone or any other noise in the cab with the FD. It made an incredible difference.

So come on Todd, what are you digging for? Don't toy with me! ;)



Kry226, good points but I dont think any of us have experiencing vibration issues with the FD. They work great in that regard!



Just block the tires Front & Rear , set Parking brake, Slowly release Clutch. the noise will disappear under load. . Or should disappear. Now if you are experiencing vibrations... That needs to be Look into...
 
Just block the tires Front & Rear , set Parking brake, Slowly release Clutch. the noise will disappear under load. . Or should disappear. Now if you are experiencing vibrations... That needs to be Look into...



Can anybody that still has a FD do this test?

Sounds like we really need to run one on a dyno. .
 
i have to say i am blown away by the support of genos and fluidamper. i have 3 fluidampers on three different trucks. 06 cummins, 99 powerstroke, and the 97 cummins i had. the difference the damper made on all of them was impressive and i have been really happy with them.



i have not dealt with fluidamper directly, and have only ever ordered parts online from genos, but im happy to see that both are stepping up and really trying to help solve the issue being discussed. this kind of support only makes me that much happier that i have purchased products from both companies.
 
Just block the tires Front & Rear , set Parking brake, Slowly release Clutch. the noise will disappear under load. . Or should disappear. Now if you are experiencing vibrations... That needs to be Look into...

Todd,

I didn't load mine like that, but the noise was evident under load on the road until about 2000 rpm. Over 2000 rpm, I couldn't hear it, possibly due to my poor hearing (Too many years of shooting and airtools) or the exhaust note became louder than the noise. Didn't seem to make a difference what gear I was in, or whether the T/C clutch was locked or not. What was also evident was a very distinct rpm related rapping noise coasting from about 1500 rpm back down to idle. The noise was virtually identical with both F/D's that I tried.
 
i have to say i am blown away by the support of genos and fluidamper. i have 3 fluidampers on three different trucks. 06 cummins, 99 powerstroke, and the 97 cummins i had. the difference the damper made on all of them was impressive and i have been really happy with them.



i have not dealt with fluidamper directly, and have only ever ordered parts online from genos, but im happy to see that both are stepping up and really trying to help solve the issue being discussed. this kind of support only makes me that much happier that i have purchased products from both companies.



I have to agree. Both parties have exceeded my expectations, and I'm anxious to know what Ivan finds after testing the ones I tried.
 
i have been thinking about this and here are my thoughts.



it is difficult to believe that a person would recieve 2 faulty products in a row. its possible but unlikely. since the fluidamper quiets the engine down i would suspect it is a problem that cannot be heard with the factory damper due to changes in the noise/performance of the engine.



i have not listened to the audio clips yet but off the top of my head i would think that possibly it is cam slap. all engines have it it just cannot always be heard. im recalling a time when i met some people that were working with bus engines, they were converting them from diesel to cng and they had a display talking about the various aspects. while i was there i they started and ran the engine and i was talking to one of the designers about the whole setup. the engine was very quiet on cng and i could hear a loud rythymic metalic tick. asking the designer what it was, i was informed that it was cam slap that could not be heard over the other engine noises when it was a diesel. since then i have noticed other instances of cam slap. my last truck i could hear it only with the oil fill cap removed. cam slap does not fit the bill perfectly but i think could be a possibility.
 
No, I don't believe that is correct. In my case, the overall noise level was much higher, not lower. The truck is definitely quieter with the stock pulley. Not quite as smooth, but definitely quieter.
 
Prairie Dog's link sounds to me just like gear slap from an out of synch CP-3. I wonder if the FD just smoothes the torsional spikes enough that it enhances the CP-3 compression spikes.



Possibility that retiming the CP-3 may change the noise somewhat.



Maybe thats the difference and why every single truck does not exhibit the same symptoms?



There also exists the possibility that the FD is so efficient at removing the torsional spikes at the crank that the CP-3 ends up being the culprit and gear noise is the natural result.
 
Prairie Dog's link sounds to me just like gear slap from an out of synch CP-3. I wonder if the FD just smoothes the torsional spikes enough that it enhances the CP-3 compression spikes.



Possibility that retiming the CP-3 may change the noise somewhat.



Maybe thats the difference and why every single truck does not exhibit the same symptoms?



There also exists the possibility that the FD is so efficient at removing the torsional spikes at the crank that the CP-3 ends up being the culprit and gear noise is the natural result.



Just a thought, could it possibly be the AC compressor?
 
CP3 is quite. . theres's nothing to make knock in the Video. The drive motor on the test bench is louder... You do hear a whined form the GP. If your CP3 is knocking or you hear it whining over the engine, replacement or it time to R/R. I would post video but the Test bench is build by Me and use in several applications for our custom build Pumps for just about any Industry from HP too down stream injection... So its private.
 
TC, what do you mean by "You do hear a whined form the GP'? (pesky predictive text?)

JJPage, your right, that's exactly what a bad compressor sounds like but mine was off and makes no sound at all even when running (which is rare in W. Wa. state :( ).

FWIW, I've listened very closely to the CP3 with a mechanics stethoscpoe and it's very quiet - just a smooth whirring sound.

BTW, I only have 78k on the truck.
 
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AC compressor is possible if its the bearing on the clutch. Should be able to remove that by removing the belt.



Has anybody tried running the FD with the belt off to remove all the accessories noise? That would limit it to something in the FD or the gear drive.



The noise I am talking about is not in the CP-3, its in the gear drive of the CP-3. What I am hearing on the link is not a knock but more reminiscent of gear slap from an out of phase IP.
 
I ran the eng for a short time without the belt and could still hear the noise.
If it were an easy thing to re-phase (?) the CP3 I'd be all for it but I've never messed with it. .
 
Ivan called me today and we had a very good conversation about the noise issue. I dropped the second damper off with Andy at Genos last Friday afternoon, and they were going to install it on one of their trucks to test. Not sure if they've had the opportunity to do so yet. I described to Ivan in detail the conditions that, on my truck, would produce the noise, and the diagnostic procedures I used. From our conversation, its clear that he is dead serious about finding the answer to the problem and promised he would keep me in the loop. I'm pleased, to say the least, that FD is working on this, because the damper definitely did quell some vibration, both at idle and mid-range under load, and when they come up with a fix, I will be in line to purchase another.
 
AC compressor is possible if its the bearing on the clutch. Should be able to remove that by removing the belt.

Has anybody tried running the FD with the belt off to remove all the accessories noise? That would limit it to something in the FD or the gear drive.

The noise I am talking about is not in the CP-3, its in the gear drive of the CP-3. What I am hearing on the link is not a knock but more reminiscent of gear slap from an out of phase IP.

I've been in the auto repair business for 34 years now, not in diesel repair, but primarily German autos, and have learned enough and seen enough never to discount another idea. The CP-3 noise certainly is a possibility, but when listening to mine with a stethoscope, the actual source of the knocking noise appeared to be loudest right in front of the FD. I used an ordinary (non-electronic) stethoscope with the probe removed, just the open airtube, so that I could listen up close to the rotating components and not make contact with anything. My intuition would be that if the FD smooths out the firing pulses, wouldn't that serve to reduce pressure spikes from the CP-3? Don't know the answer to that one, just looking for answers.
 
I had no problem with mine after 100. 000 miles, maybe Cummins put a different crank in your truck!, so stock damper would work, and one supposed to be won't, just a hunch, as it is a change over year

Rick
 
My intuition would be that if the FD smooths out the firing pulses, wouldn't that serve to reduce pressure spikes from the CP-3?



So the cam and CP-3 are gear driven right off the crank. The small gear on the crank would be directly behind the FD. The CP-3 is the fartherest from the crank but it will have the highest torsional spikes due to the pressure it builds. The cam is also going to have to spikes there as the the vales open.



I am wondering if the crank is so smoothed out that all the other gear driven components are introducing gear slap noise to the point it can easily be heard? The FD will smooth crank spikes but the cam and IP will generate their own and possibly feed back?



Just a thought for a possible source.
 
No way the CP3 is causing the noise (Unless its on its way out) There are 3 pistons that are constantly under pressure or Spring force,3 tappets that are driven by a cam that is rotated by the shaft ,which is supported by front and rear bushings. . Its quite. . I tried to post video ,but the sound was so quite you could not even hear it, the GP will whine but cannot be heard over engine combustion knock.
 
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