I run an 05 with the Predator at 85hp or 100hp. I works great when the engine temp is below say 180F, but when I reach that point and higher the engine sounds like my 3306 Cat when I start it with to much ether on a cold mourning. Between 1900 rpm and 2200rpm it makes the most knocking noise but sometimes it comes and goes also. Before the Predator I had a J/A on it and hated the wait for operating temps to reach 180, so I removed it. If I remove the Predator the knock isn't as bad but is still there.

The dealer claims I have the most recent updates and tell me it's normal diesel sound. My LB7 never sounded this loud. It also seems to lose power during all this knocking, because it pulls harder without the knock below 180F.

I've searched and read a lot of the post regarding this, any one have an idea?

Mine does this on 100 hp.....still trying to figure out if this is normal....really like it otherwise...just hope it isn't hurting anything. Like I said....sure runs good with the predator set on 100 hp!

That's odd that it would start knocking as the engine reaches operating temp. My powerpup is the opposite, it knocks till the water temp gets to 180degrees. I'd call predator and talk to them about that.

almost all programs will add some noise to the vehicle, theres just not much that can be done about it as you advancing the timing and increasing the fuel - noise is ok as long as its running ok and everything else is fine, youve got to remember that these are diesel trucks and not little toyotas

I'm with tbone, these are diesels - diesels make noise. But I guess it depends on how much or how loud the noise is. The LLY uses pilot injection at the lower rpm's, when it hits a certain point the pilot injection is replaced by ??? (I can't remember the technical discription) the actual injectors which create that 'pop' noise that is a the signature sound of a diesel.... also referred to as having the rods knocking. (If I explained that wrong - please correct me)

I have mine on 85 with no problems, I have run on 100 a little but haven't had excessive noise.

Sure I understand a diesel makes more noise then a gas engine, I have two Cats, four cummins, one isuzu, and the duramax, and none of then knock like this as you apply throttle at a cetain range then stop at a higher rpm.

My old 02 duramax was stacked with programs and still didn't sound this loud. It just seems odd that is occurs at a certain rpm range.

I called Predator and the tech state it should sound no different then stock.

And the thing that gets me is the fact that power seems to be down when this occurs.

youve got to remember that these are diesel trucks and not little toyotasIs that the same as a "little Izuzu" ??:D

Diesel engines make more noise - but the dmax uses a sophisticated common rail design with pilot injection till 2500 RPM. So why all these noise? I had a 15 year old Landcruiser inline six with simple direct injection with no drone at any RPM. I guess GM has overdone the parameter programming to win the torque war. The old LB7 design was fine and quiet, I should have bought that one. But after reading what everybody said about the new LLY - that it is quieter and quicker I bought the new one - and I am NOT really happy with my decision. Both the LB7 and LLY I tested before ordering my 2005 were more quiet...so there MUST be something wrong with the new PCM setup, even other exhaust, intake or programmers can't change that. Don't know what to do next

Thanks for the info. I guess I'll just plug in the J/A also, set it and the predator to max and have fun.

Steve Palauskas (http://dieselplace.com/forum/member.php?u=9209):

I have the same problem you are explaining on my 05 DA. I have an Edge Attitude and the knocking kicks in pretty much any time. I have not checked the temp when it does, but maybe changing out the thermostat may work??? I don't know. I hope it could be fixed so I can have fun with the Edge.

I have noticed that sometimes it does accelerate without the knocking.

Diesel engines make more noise - but the dmax uses a sophisticated common rail design with pilot injection till 2500 RPM. So why all these noise? I had a 15 year old Landcruiser inline six with simple direct injection with no drone at any RPM. I guess GM has overdone the parameter programming to win the torque war. The old LB7 design was fine and quiet, I should have bought that one. But after reading what everybody said about the new LLY - that it is quieter and quicker I bought the new one - and I am NOT really happy with my decision. Both the LB7 and LLY I tested before ordering my 2005 were more quiet...so there MUST be something wrong with the new PCM setup, even other exhaust, intake or programmers can't change that. Don't know what to do next
Drives me crazy as well. Sometimes I wish I had kept my LB7. I have had my truck back to the dealer many times and the always say that is how it is suppose to sound. Even stock my truck sounds like it is a gasser running on low octane fuel. Drives me insane all the way down the highway. I actually like it when the pilot injectors cut out!

I think GM has a problem with the factory programing and will not admit it. I am hoping Edge or somebody will release a program to cure these issues. On my truck the Juice does seem to quiet down the noise at least initially. After a few miles it seems to come back. I have a hard time beliving the noise I am hearing is not doing damage to my truck. I just does not sound right.

I called the predator people, they said it should make the broken valve in the combustion chamber sound. Then when I told them it was intermitten he had no answer. So today I'm running with the predator on max with the J/A on 5. We'll see how it sounds.

Mine makes similar noise with the hypertech set at the highest level 3. I had the J/A and hated the knock and surge at 160-180 degrees. Hypertech also does this but not nearly as bad. It also dosent add the numbers that the Edge does. I have no pcm update as of yet.

Diesel engines make more noise - but the dmax uses a sophisticated common rail design with pilot injection till 2500 RPM. So why all these noise? I had a 15 year old Landcruiser inline six with simple direct injection with no drone at any RPM. I guess GM has overdone the parameter programming to win the torque war. The old LB7 design was fine and quiet, I should have bought that one. But after reading what everybody said about the new LLY - that it is quieter and quicker I bought the new one - and I am NOT really happy with my decision. Both the LB7 and LLY I tested before ordering my 2005 were more quiet...so there MUST be something wrong with the new PCM setup, even other exhaust, intake or programmers can't change that. Don't know what to do next I live in CA. :) Wanna trade?:)