Since owning my new 05 cc sb 6.0 lariet truck, I have had a stutter or miss while pulling one of the passes near me. Everytime I have gone over this pass, the truck has started bucking and jerking. Sometimes real bad, sometimes just a slight but continuous bad vibration, and sometimes it went from good to bad, sometimes bad to not-so-bad. Put a recorder on truck and got ford engineering involved, showed up yesterday, and found what I was talking about.

The ford engineers loved this pass, and apparently my truck. They spent most of the day yesterday driving it repeatedly over the pass getting the truck to act up. They put close to 200 miles on the truck, and left my truck at the dealership for me to pick up with so little fuel in it that none of the guages worked, just a low fuel warning light on the guage cluster. Their comment to the dealership was they were aware of the problem but were unable to duplicate due to no satisfactory test conditions back east. They had all kinds of recorders and diagnostics equipment on the truck, and left with info that could help them find a fix.


This is there response.

"It is a pressure imbalance on the turbo vanes, Not an unbalanced turbo, but an unbalanced pressure across the turbo, and is normal. They know about it, and are trying to devise a cure. It is caused when the engine starts to lug, and revs drop into the 1700 rpm range. The only cure at the moment exceeds emissions, and so they won't do it. They claim it is not harmful, and not worry." I called (SNIP) you don't have 500+ ftlbs of torque slamming into a driveline without stressing components." They agreed, but their hands are tied by the feds.

Their temporary solution is to get it out of this rpm range. Get on the fuel, downshift, or slow down more.

Now I need to get the dealership to fork over the cash for the tank of fuel, and change my warranty and add about 400 miles to it for all the mileage that has accrued while ford has been driving it in the 5 time in shop in the first 3 weeks of ownership.

 

It must be tough to be an automotive engineer these days. By the time your bosses, the EPA and the stockholders are through with you, you're never allowed to fix any problems. I'm sure they'll work these findings into some future design, but that obviously doesn't help present owners. All you can ever tell them is "yeah, we see it, and there's nothing we can do about it." Not very satisfying.

Duncan

 

I can feel for you as I am going through the same "normal" things with other issues. Normal means 'we have no clue what is wrong so we will call it normal in the hopes you buy the line and go away". See if your dealer will let you take a demo truck and go to the same place and see if that one does it. If it doesn't ask service why. I have not seen this issue yet on my '05 so you may just have a problem child. If you get no reasonable answer at that point you may have to go down the buy back trail.

There is nothing more aggrivating to me than to have it insinuated that I am nuts or stupid (true or not) by someone who I paid several thousand dollars to for something that should work as advertised.

Good luck!

 

I would start documenting every conversation you've had with them right now while it's fresh in your mind. Document every little detail as much as possible. Get the dealer behind you, you may need them in the future. They aren't the bad guy in this. I'd also ask Ford for a date as to when you can expect a resolution. And it couldn't hurt to start reading all you can regarding buybacks, lemon laws, etc.

IMO a consumer should expect their vehicle to perform under most normal circumstances without "bucking". Good luck and keep us informed.

 

How tall is that pass? I've had my 04' up to 6800 feet right at about 1700rpm without any stutter.

One thing I did notice is that the "Zoodad mod" helps at altitude. The air is thin, and I don't think they've designed means to get enough air to/through the intake. As a test without modifying the forward core support, you could just remove the air filter for that stretch. (I don't think you're gonna catch too many bumble bees flying around this time of year.) You should get some more air flow. Also, what are the ambient temps when you're driving over the great divide? Could you have some icing happening in the intake system?

Aside from where my thoughts were going, If you accellerate, does the stutter go away?

Hmm? The current fix for your situation is not approved by the EPA? Did they say what the fix was? EGR?

 

Boy jfralph...I was hoping as much as you that everything would work out really good with this new '05 truck.

Glad to hear though that at least The Ford boys tested the heck out of it and at least had some discovery. Common courtesy though would have been to fill 'er up and maybe throw in a new shiney coffee cup or two.

My totaly unscientific observation so far on the '05 is that as the 3rd generation (MY) 6.0 hits the street, a huge amount of the old issues have vanished. However, we have already seen (as with your truck) that a couple of the biggies are still haunting you guys.

Wouldn't surprise me a bit if some of it boils down to that stupid EGR valve that they and 6.0 owners are forced to live with. At what cost I wonder though?

Good luck and plese keep us informed.

 

I have pulled my trailer to 11900 unreal the power ....I live at 6k and go to 10k all the time so I am used to what it feels like with no power in a gas motor.....I have never been down that low on the RPM

 

What they are talking is a characteristic of all variable vane turbos - it can be engineered out, but it takes a fair bit of work.

This is why I doubt on future models we will see Variable Vane Turbos...

In the mean time, I wouldn't be overly worried about the stutter - it should not cause any damage, but try to drive around it if possible.

If Ford Engineering came out to visit you, and your truck, they will be working on a fix - believe me.

Did you happen to get the engineers business card?
A follow up call to them never hurts, just ask them how they are going with a fix, if they need to drive your truck again etc. (prehaps suggest them to fill up the gas tank this time though...)

I personally wouldn't go down the buyback route - its really not worth worrying about, far to much effort for my liking (and you usually end up worse of in the end).

BigF350

 

A very good point and one that allows all of us to have a more in depth understanding of the issues. Now I am interested, when I get my truck, to try and duplicate this phenomenon

 

Just curious about driving habits... Since best torque is at 2200 rpm why would you let it stay at 1700 rpm, especially pulling an incline? Any motor will lug when you are pulling at low rpm.

 

does not need to get to 1750 before it starts bucking,,

we tow a 5th wheel and run in the 65 to 68 MPH range with cruise control on,, even a small overpass or hill will start the bog down process on mine in the 1900 to 2000 RPM area,, certainly not in the lugging range,, of course the 8 MPH window the cruise control offers may also play a part in the mass confusion the engine seems to be going through trying to figure out what it should be doing,,

hey my 2003 7.3 would just chug on over the hill and never give it a thought,, for a new engine with more HP and Torque you would think it could handle the small hills without any effort,,

 

IMO the 6.0 is really not in a good RPM range at 1900...the best I have found is 2300 to 2700 and it is no where near the lugging of the 7.3...two very different motors.
If you drive them the same you will be disappointed in the 6.0 It does not matter how much HP/TQ a motor has ….it does matter that you know where it has it…..

 

I think that you guys may be putting to much into this RPM senerio as when this stutter is occuring the boost is 10-13 psi if the boost gets above 13 then there is no stutter. I have had the boost get to 15psi at around 1900rpm and it will pull the steepest hill you can find and not shift out of overdrive and the boost will continue to rise to 25psi and never miss a beat. It only occurs when the boost range is 10-13. If it was a load issue or an RPM issue then you would think that it would occur more when there is more of a load but that is not the case. But I may be wrong as you all seem to be very knowledgable. We apreciate all your input, kind of strange that we get more correct information from this web site than our service dept.

 

You are spot on with the boost bit.
And you are also right, it is strange that we get more info here than our service dept.

 

I played with my truck to get it to take off from a stop and boost is related to RPM if you think about it. The turbo cannot spin without the motor turning and the more the motor turns the more force (exhaust) it sends to the turbo (hence building boost by pushing harder on the throttle).

That being said, when I was talking to the Field Service Rep he said the power band on the 6.0 is different (higher) than the 7.3 and not to lug it down the same. If I remember right it was about 300 RPM higher on the low side (begining) so he said to wrap it up a little more for the power to kick in. If you do a search you will find where the power band now sits (something like 1900 to 3300), I compare it to the difference between a CAT and a Cummins (the 7.3 being closer to a CAT). I think the stutter you are feeling is the motor trying to hit it's power band under load and not liking it.
Just my 2 cents......