I was under the impression that the 6.0s were supposed to have reduced the noise level. While at a drive in today, I had to shut down to place my order. Is this just me or have others had this happen to them?? Not that I'm complaining, I was grinning the whole time.

 

The noise level depends on when it was built and what flash it has. The earlier models had pilot injection and vere pretty quiet. Later flashes went to using EGR strategy to quiet them down, but it isn't as good. They've been reworking that strategy ever since ditching pilot injection because of injector malfunctions with the pilot turned on. That's what I've gathered, anyway. Mine's in the middle somewhere, a Feb 2004 Engine with its unmolested flash. It isn't as quiet as some, but it isn't as loud as others. Go figure.

 

It also has a lot to do with the building you are at, how the sound bounces off it and reflects to adjacent walls....one drive up sounds quieter than another.

 

Tim, is it time for another decibel reading? Could you do that again?

 

I shut down to order at drive ins just to be courteous. I wouldn't want to upset the person handling my food.

 

I do not have the equipment, bummer and cannot get it!

 

The first '03s were quiet enough to pass the "drive-thru test" - one of the selling points of the 6.0 and one of the reasons I bought one. The very first place I went after taking delivery of the truck was an Arby's drive-thru with the worst possible acoustics, between two buildings. (On our 7.3 trucks I actually had to turn the engine off again at the pickup window because they couldn't hear me, or the next person back in the ordering lane!) The 6.0L passed with flying colors!! That was really cool. I was impressed.

Then Ford took away pilot injection with a subsequent reflash and I'm back to owning a loud diesel. It's not as loud as the 7.3L trucks, but it can't even remotely pass the drive-thru test any more. Oh well, maybe they'll do some more thorough engineering on the next engine.

Duncan

 

What is funny...we all talk about the quietness...and then put DP's and remove the CAT and 5" and ...

 

My 05 was loud when i got it....Ford did my first oil change with motorcraft oil...Still loud .then i decided to change to Shell 15/40 Rotella T oil..The clacking noise level reduced...My most recent oil change @2800 miles 3 days ago i switched to Shell rotella-t synthetic 5w/40...Much quieter and the clacking is more even I also got 19.5 mph@60mph stock program

I think the oil makes a difference

 

IMO it makes a very big difference, but without proof most do not want to spend the money.

 

Well i don't do much driving..this truck is my pleasure vehicle...Walmart has the oil for 12.87 per gallon...I put 13 quarts in and the level is between min + max...Its a pleasure to drive....except(it still smokes)

 

Not me! Unlike a lot of people (i.e. *all* owners of older Cummins Dodges!) I don't want to own a diesel *because* it's loud, that's just an unpleasant side-effect. I also don't put in a performance chip just so I can make big clouds of smoke - I'd be happy if my truck never wasted fuel like that. (The 6.0L is actually very good about that, but not perfect yet.)

I'll tell you one thing that quieted down the clatter of the '97 F250HD: running a high percentage (70%) of biodiesel in it. After 120K miles of experience in it, I'm pretty sure I know how loud it usually is and so it wasn't just wishful thinking that it was quieter on the high percentage of the slippery stuff. The day I added 10 gallons of straight biodiesel to the couple of gallons of regular diesel in the tank of the '82 M-B 300SD while it was idling, you could actually *hear* the engine noise almost go away as the biodiesel made its way to the engine! Amazing.

With the 7 remaining early doomed injectors injectors in my '03 I don't dare give Ford an excuse to hose me, so I won't be running biodiesel in that until it's out of warranty in 60K more miles. But I can't wait to hear how quiet it can get with the alternative fuel. Can it get back down to the levels it was at when it had pilot injection? Maybe, just maybe...

Duncan

 

I have access to a hand held meter at work. Where do you want it measured and at what distance?

Steve

 

Tim posted some numbers on that about a year ago. He measured it outside the vehicle standing at the side, standing at the front, standing 25 feet away and up close. Then measured different trucks, 6.0, Cummins, Duramax etc.

Tim do you remember the scenario?

 

Found it this was on an 03


It seems our 6.0 really is quiet, took all the readings with the same calibrated sound meter (slow setting). All readings were taken with A/C and stereo off, no conversation. Outside readings were taken 10' directly in front of truck and 25' away at a 45 degree angle, about where my neighbor's bedroom window is. Readings on my 2001 F-250 Crew Cab V-10 gasser were included for comparison. All vehicles were crew cab, and built within the last six weeks. From what I can tell, the F-250 still had split shot injection, raising idle 100 RPM or more and there was a noticable change in the tone of the enging noise. The temp was 59 deg, humidity 60%, if that matters.


Ford F-250 6.0L PowerStroke Diesel (no hood insulation)
Inside @ idle 52 db
Inside @ 70 MPH 68 db
Outside 25' @ 45 deg 62 db
Outside 10' @ 0 deg. 72 db

Chevrolet Sierra 2500HD 6.6L Duramax Diesel(hood insulation)
Inside @ idle 54 db
Inside @ 70 MPH 68 db
Outside 25' @ 45 deg 65 db
Outside 10' @ 0 deg. 71 db

Dodge Ram 2500 5.9L Cummins HO Diesel (no hood insulation)
Inside @ idle 58 db
Inside @ 70 MPH 70 db
Outside 25' @ 45 deg 66 db
Outside 10' @ 0 deg. 69 db

Ford F-250 6.8L Triton V-10 (2001, mine)
Inside @ idle 45 db
Inside @ 70 MPH 68 db
Outside 25' @ 45 deg 58 db
Outside 10' @ 0 deg. 63 db