Just wondering if Ford has fixed the 1800-2000 RPM noise on the newer engines. Seems like it would have been easy to do, but...

 

I have reported this about my 05 V10 but called it resonance rather than Flutter.

My truck does not do it naturally, I have to deliberatly set up the condition. The entire exhaust system on the 2005 3 valve V10 is not in any way similar to the 99-04 system.

There is a particular rpm and speed under uphill loading that will generate a distinct resonance that your ears can hear and feet and butt can feel. Since I have the 4.30:1 rear end I will assume the owners with 4.10:1 will have this resonance at a different rpm than I do.

Unless I deliberatly hold that particular rpm the resonance is very marrow banded. In other words 20-50 rpm higher or lower and it is not noticable at all.

My experiance with the 2001 V10 and flutter was that it was much broader range of rpm and more tinny annoying condition. This one is a much lower tone and the "depth" of the vibration is not startling or annoying.

I am convinced it is not caused by the same set of circumstances that the "Y" pipe induced the Flutter in the previous systems. This to me seems to be more associated with the very long length of the collector to Muffler run. I bet that short bed owners probably will not be able to duplicate the sound.

 

Thanks for the reply.
Thinking about the transmission inspection plate type of flutter.

 

I have a totally stock '01 and I have no "resonances" - at all. I had the "flutter" which was the aluminum cover on the front of the bell housing. I have the restricted Y-pipe.

Other than that, no combination of load, RPM or gear (auto) makes it resonate at all. The exhaust is "hissy" ... but that's all.

Just wanted to make that one statement. I have the stock Y-pipe and no resonances... so I don't think it's the Y-pipe doing it - the natural imbalance of a 10 cylinder engine is more likely.

I wonder if any machinists (or machines) exist that can really balance a V10 ?

art k.

PS: My truck is an '01 made in 10/00, found on a dealer's lot with 25 miles on it in June of 2002. It had all the little TSB's done to it, like the radiator hose clamps, but I can't tell if they changed the Y-pipe at all and can't determine if it's not the original.

 

I have reported a few times all the different noises on my 01 that we all though of as "flutter" but the most annoying resonance (sympathetic vibration?) was indeed from my trany inspection plate.

I did have certain rpms in OD, under load, that the exhaust system exhibted an annoying "flutter"... Ford claimed to have a reflash that was the "cure" but we rapidly found out that the "cure" really was to lower the engine power to a point where you couldn't duplicate the sound any more because you had to be in 3rd gear to get any where!

My code was IGW0 and I had a standing threat with my Ford service manager that if they ever changed my PCM or reflashed my computer then they would be buying back my truck...and I was very serious!

I consider myself a pretty good tech and self taught exhaust expert...flow dynamics wise. I believe the tightly necked down 90 degree input angle of the "Y" pipe was the culprit in cases of true "flutter"... and that is was simply another example of sympathetic vibration partly induced for reasons coincedental to valve overlap, wierd V10 power pulses and the length of travel from some right bank cylinders in relation to left bake cylinders meeting at the "Y".

I have a two into one exhaust system I fabricated on a twin cylinder motor cycle engine that I can cause to "flutter" under certain rpms and loads. And with another set of two to one pipes(longer and smaller diameter) I can make it "crack" such a sharp high note you would think I was riding a machine gun!

 

Fred, you are absolutely right in everything you said. I'll have to check my code now

And, that caveat I gave is telling too, I bought the truck in 06/02, it was on the lot since late 2000. Who knows what they changed on it, so they could make a few extra bucks in labor on a truck sitting on the lot? I immediately saw the hose clamps on the radiator, so that means they at least did something to it in the year+ that it sat in the lot (remember the bad radiator clamp TSB). (yeah, it might have been leaking but there was something else done from a TSB that didn't need to be done, but can't remember)

The "Y" pipe is a gross example of computer-aided-design (CAD) - taken too far... I plan on changing it after the lease is up in a year and a half

Now, the 390 I built for my '74 had a strange resonance, between the intake and exhaust, and it just hit a peak somewhere near 2400 RPM - peak torque, or around there. Maybe I just needed an H-pipe That was a homegrown design that went from two do-nothing mufflers with downturns in front of the axle, to four mufflers, the second set behind the rear axle with pipes right out under the rear bumper. I definitely got a lesson in "purge" on that project - the longer I went, the better the torque, from down low all the way up high (only 2.25" each)... and that "resonance" moved as the exhaust was lengthened ...

As to the valve-overlap, yes, 72 degrees is different than 90 - but that just means there's not as much "woo-woo-woo" to the exhaust - there's more of a constant pressure - that's where the "hissy" part comes from in my exhaust... (I am theorizing).

And you're right about the flow of the V10 exhaust - five cyls in one log.

I've noticed that people with headers don't complain about resonances, they complain about the hissy sound more than anything.

And this all has NOTHING to do with the guy's original question, but at least we're keeping it at the top

art k.

ps: been reading this site since I started thinking about buying an SD in 2000...