Hey all. I've read a ton of stuff on here and still have some questions, please bear with me.
My company work truck was a 2010 F450 chassis with the 6.4, Reading service body with an IMT crane. It's around 14,000 lbs normal weight and it ran great I put 28,000 mi on with no major issues besides lately it's been smoking like a pig due to the regen not completing due to cold weather and not being run for a long enough period between shutdowns.
I just moved into the new 2011 F450 with the 6.7. Same body and curb weight. It's a company truck so I can't mod it.
My questions,
#1 The PTO won't engage when cold. The 2010 would engage cold. Is there an engine or trans temp that locks out the PTO?
#2 Is this eligible for the 400/800 flash? I know it doesn't have it due to the manual shift indicator. I see the TSB is just for pickups?
I have noticed that the takeoff lag is MUCH more pronounce in this engine then the 6.4. I got used to the lag on the 6.4 and eased the throttle for better takeoff but the 6.7 is really bad. in comparison.
Just for the record, the best mpg I got was 9.4 in the 6.4. I only have about 100 mi of driving the 6.7 and it has 750 mi on the odometer.
Thanks, Greg

 

#1, The engine computer will not allow PTO operation before the engine reaches 140 degrees.
#2, You can not get the 400/800 flash on a chassis/cab truck. The engines are different than the pickups.

 

Thanks. That's kinda what I thought from what I read here. Nice forum here guys! I'll still keep reading and dreaming! LOL!

 

The turbo lag has been discussed here on another thread. If I have the lag on my truck I guess I can't tell it. However, no bed or weight, just a bare frame. Perhaps this will become evident with some weight and load. I'm sure you know what your truck is doing. I like to hear from other chassis cab drivers. We are kind of the lost sheep of the 6.7's, still seems like a nice rig to me. Signature shows the way truck will be when finished, can't wait..

 

Burnerman,
I hear you about the lag, mine does the same thing. The lag is worse as I go up in altitude also. Like you, this is also my company truck, the last one being an 02 F450 with the 7.3 which had no lag in comparison to this one.
Rich

 

The "lag" is very noticeable if you are coasting or very lightly on the throttle and then decide to slam on the pedal. If you slowly press down on the pedal and then hit it hard it isn't noticeable at all. It seems like "lag" probably because the transmission is deciding what gear to be in when you just slam on the pedal.

 

Yeah the lag is bad. period. I know the truck is heavy and I had lag off the line with the 6.4 also but not nearly as bad. Once the turbo boost went 30# + in the 6.4 it would pull like a fiend. In sticky situations with the 6.4 I could power brake it and get some boost up and takeoff quick. Haven't really done it yet with the 6.7 but will be soon The 6.7 is just a dog so far even after it boosts up the engine just seems to take it's sweet time pulling away. I've been easing the pedal and find it does accelerate "better". It seems that anymore then 1/2 throttle is pretty pointless. The only time mashing the pedal down does anything is at speed and kicks the trans down a gear or 2. I'm hoping the 6.7 will start to wake up a little after 1500 mi. The 6.4 seemed to get better after that milage. I really don't think it's turbo lag as even after I get 30#'s of boost the truck still doesn't have the getup and go the 6.4 did. Time will tell. It is slightly quieter then the 6.4 but the trans seems noisier but that may be the PTO. We got a service bulletin about noise in the PTO at idle.
What is the difference between the pickup 6.7 and the cab chassis 6.7? There's nothing about that in the manual and it's the same manual the pickups have. It seems that some issues could be fixed with the flash with this truck.

 

I don't put my foot in it from a stop or when coasting. You have to baby it for about 2 seconds and then it's like flipping a switch, it gets boost, and lots of it. This is when taking off, or making a turn and trying to accelerate. Any kind of normal throttle just gets an increase in time for the boost to come up. I've started driving alot in manual mode and downshifting to keep the rpm's up to avoid the lag somewhat. But that gets old also when you're doing miles of twisty mountain roads. It has great power once the turbo has lit off, but I'm not nearly as heavy as burnerman. The truck does have the latest flash also.

The difference from what I've gathered from here and other sites, is that the pickup is 400/800 rated and the C&C is 300/660 rated with a different turbo than the pickup engine. The engine is the same as the pickup engine, just tuned differently because the pickups are in a different emmissions category.

Rich

 

Rich is exactly correct. You have 300 HP and 660 ft-lbs of torque. Compared to 350/650 for your old 6.4L engine.

It's not going to pull as hard as your last truck, as this one has less power. You should see better MPGs though...

 

Great! Less power in the same size truck! LOL! So is the pickup engine tuned for cleaner emissions and more power or the heavier trucks less stingent emissions and less power, or visa versa? I'm confused. It seems to me that a cab/chassis is going to be a heavy work truck be it a service crane, dump truck or other constantly loaded hauler. The pickups, with the exclusion of the dually's, will log more unladen miles. I understand you guys pull alot of heavy trailers with the dually's. Why the power flip? The power output was perfect for the old truck. Trust me the 6.7 is no slouch but I can feel the difference for sure. The truck is outfitted the exact same,16,500 # package with towing,4:30 limited slip rear,4x4, IMT 2020 crane, Reading utility body with 1500 # hyd liftgate and an 8000# Warn winch. Curb weight from Reading on the 6.4 was 14,000#'s IIRC. With my tools and parts and my butt I'm sitting around 14,700#'s. I gotta pull the delv slip to see what the 6.7 weighs. I gotta hit the scale this spring and get a straight reading.
For a $7800 option you'd think they'd at least have the 6.7 put out equal power as the 6.4. I moved into the truck because of the interior. The split bench is awesome compared to the standard bench seat in the old 6.4. It's a much easier to drive truck, comfort and visibility wise. I was also hoping the DEF system would work better then the regen system in the old 6.4. With my job I don't get to drive it long enough to finish a regen. Once in 28,000mi did I ever see the Exhaust Cleaning Complete. The 6.4 was really starting to smoke quite a bit during regen attempts.
I guess I'll get used to it. It's not terrible but pulling out into traffic is tricky! I had a guy wave me out to make a left, he was 100yds out and going slow, It took me so long to get across the lane he had to hit the brakes. That would've never happened in any of my older trucks. I've got side curtain airbags now so I guess I shouldn't give a hoot! lol The mpg is 1or 2 mpg higher already then the 6.4 so the boss may be happy this year.

 

Okay, so you're only down 25 HP then. The heavier cab/chassis 6.4L trucks only got 325 HP, they were also derated from the pickup truck engines. Not completely sure why, but the general consensus seems to think for long term durability reasons.

Remember that this truck still has a DPF and uses a very similar method to regenerate the filter. The SCR system that uses DEF is completely different, and is why you have a much smaller EGR system and much better efficiency.

Overall I believe it's still a better motor. Sorry to hear you're disappointed about the power, I guess I'd be disappointed too.

 

I edited my previos post. I'll get used to it's power. It still seems funny about the power trade off. Pickup owners who haul want long term durability also. The DEF system itself should improve engine life itself, no? The EGR system and regen setup on the 6.4 was hard on the engine I was told. Anyway it seems strange to me the heavy haulers get less power. The 400/800 would boost this truck up 100hp and 180ft#'s that would be a very noticable difference!
.

 

You guys are starting to scare me!!. Hope I didn't make a $43,000 mistake when I hook up the 5er. Only have 350 miles on it. Unfortunately it will still be 6-8 weeks before I get it done so I can hook up the 5er. Maybe all of us cc guys need to get on Ford's behind about the turbo lag situation. Maybe they could address it someway with a software upgrade. I have not experienced the lag yet, but have nothing but a spare tire on the frame. I'm sure you all know exactly what you're talking about. So, if you use light throttle while accelerating does this make the lag not happen? Of course I realize how easy it is to find you need to merge in traffic quicker than you had thought. No matter how hard you try you'll make that mistake sooner or later. I'll talk to my young diesel mechanic this week, I think the dealer has paid to send him to every factory school. He loves to dig into these issues and is quite inquisitive.

 

Hey Rich. My truck was built 11 Jan. Would it already have the flash you're talking about?

 

As far as I know it should. Mine was built in August so it didn't have the latest flash when I got it in December.
Rich