That's probably true, but displacement isn't everything... apparently the 6.7's HP/L doesn't scale linearly off the 5.9 due to geometric relationships such as rod/stroke ratio.

5.9s can handle 200 HP/L reasonably well, while 6.7s seem to release the Expensive Smoke from the block around 160 HP/L

 

Well I guess I'll chime in.....

I'm bumping 4K on my 6.7 (I know, it ain't much), but so far, no check engine light (knock on wood) and I'm averaging 17.5-18MPG in mixed city/interstate driving.

Drove to Vegas and back with my 11K# toy hauler and set the cruise control, never could do that with the 96. Good news was it maintained at least 65 MPH up several long 6% grades, never dropped below 4th and the E-brake is sweeet! Bad news is I averaged about 9.5 MPG towing....so I'm really hoping the mileage improves as the motor breaks in.

So far I'm really happy with it.....

 

Cowhand, nice to hear from a fellow 909'er. I have only 1200 on mine and sure don't get that good city/hwy mpg like you. More like 12/13. No CEL's either. I just did my first tow to/from Glamis (about 400 miles). I got 9.2 mpg towing. I was shocked at how bad that was and only got 305 miles out of the tank. I have a 21" toyhauler (<10K lbs.) and drove 65 mph.

Other than mpg, the truck is awesome, I set the cruise at 65 and on the twisty turny grade on the 60 near the 10, it just pretty much stayed there and the tranny would downshift and e-brake as needed. It was sweet and only varied 5 mph, and was impressive. Bad mpg, but power is on tap anytime... I hope it breaks in and the FE improves. Nice to hear that I'm not an anomoly here on the efficiency.

 

Look the thing is our state laws might be one way NOW, but they could change overnight and they COULD start the emissions DYNO on ALL the diesel trucks...

All I am saying is that I don't agree with the crap on my truck and it doesn't make sense, but if they stiffin up the laws and start requiring Particulate filters on all diesels than I'd rather have a truck BUILT and PROGRAMMED for it, than trying to retrofit it to a 5.9...

Just my .02!

 

They did build one designed for EPA.The 6.7.Its not a retro fit.

 

What is all this BS about retrofitting? No one will be retrofitting anything. The bottom line is, if a truck came w/ just a muffler(03-04s) all it has to have is just a muffler. The only guys that are questionable are the ones pulling cats, DPFs or running strait pipes, they might have to put their stuff back on is all.

 

Thats what I was trying to say.Glad you just put it out there Was wondering where in the world folkes thought you would have to retro previous year models.The EPA equipment they came with for there year model has to be in place and working.You know it is illegal to trade or sell a vehicle with said equipment removed.Some dealers go over them from head to toe cause they have taken them in on trade and vehicle sold,checked and flunked and THEY were held liable for putting all removed equipment back on etc.

 

To take it a step further, I don't think retrofitting is the issue. The issue can be that the truck has to adhere to a standard that is relative to their manufactured date plus factored wear. I see alot of guys with different injectors, CAIs, turbos and other parts besides the visual exhaust deletes that can throw up a flag on a visual inspection or even cause a vehicle to fail the sniffer emissions.

Believe me, I have a 70 Mach 1 and until this June I had to get it through emissions and it was a nightmare. Not only did I have to do the yearly dyno test, there was a visual inspection as well for a car I might drive 500 miles a year. To make matters worse, in AZ your only get a one-time waiver, after that you have to pass emissions or no registration.

Like it was stated earlier, I'm not a fan of this added emissions junk especially when there's clean fuel sources out there, but the fact is driving is a privilege and not a right (I hate that part too). If the man chooses to play hard ball, right or wrong, agree or disagree, they can make things expensive and miserable.

If you live in the boonies, you're lucky and I'm envious. But if you're one of us in a larger metropolitan area, things are only going to get tougher in terms of what can come out of our tailpipes.

 

That is too much $$ for that 5.9, I'd get the newest flashes for that 6.7, keep it stock and see if things improve.

Retrofit? Maybe not for our trucks yet, but don't put anything past CA.

http://findarticles.com/p/articles/m..._4/ai_65950143

http://findarticles.com/p/articles/m..._6/ai_84667075

 

You guys are NOT listening, this is the goverment we are talking about...

Everybody is aware of what LAWs we have now, like if it did'nt have it on from factory they can't make me put it on...

Well thats wrong... They can make you ADD particulate filters, cats, and whatever if they pass a law on ALL diesel trucks NO MATTER what year or what FACTORY equipment it had...

So just because it did'nt have a Particulate Filter installed on you 01',03', or 05' DOESN'T MEAN THEY CAN'T REQUIRE ONE IN THE NEXT COUPLE OF YEARS...

And from what I understand, you can either RETROFIT it or sell it overseas and upgrade to a EPA friendly DIESEL!!!

So all I can say to all the 6.7 owners is at least we have a truck built to perform with the EPA requirements...

They wouldn't go through all the bull$h%& with these trucks if there were no up and coming changes in EPA laws!!!

It is coming so don't fool yourselves!!!

 

Back to the original question. I had a 6.7 and traded it back 4 months later for a 5.9. I did not do my research on the 6.7 before I bought it in May of 07. Yes, the DPF and new emissions standards is here to stay. If you plan on keeping the rig for a long time the 5.9 is probably the safest bet. You will lose money by trading, however you may be better to trade now and not have to worry about the expense of DPF/emissions problems after your warrenty has expired.
I could not take a chance of being in a hay field pulling a trailer or up in the remote mountains in here in Idaho pulling horses when my DPF indicated it was 80 percent full and needed to be ran on the highway for 45 minutes. What a bunch of bull!
The 6.7 is a great engine but the DPF system is flawed.
Hopefully the new recall will fix the problems with the 6.7 system.

 

The flashes have allready fix almost 99% of problems with the dpf.

 

Nobody is mentioning the fact that for EACH fillup of fuel, FIVE QUARTS of fuel is used for regeneration! That is 4 dollars each fill up, for you to go nowhere! consider it an added TAX to operate your truck payable to the state, federal tax, OPEC and the oil companies. Why in the world would anyone want to pay extra money if they didnt have to!
If people were asked to pay a highway tax of 4 dollars each time you fill up people would be outragesbut guess what you are paying that and you dont even know it...all so you can have 2 extra gears...HEL...LLLOW!!!

 

That is very interesting and makes sense. How do you know it takes 5 quarts? Assuming the information is valid that pretty much sucks and hadn't thought of that fuel penalty possibility in that way. In addition to the per tank penalty we all ready paid about $1k for the BLUETEC system in the first place. Investments in the future? So we don't have to add all this down the road? I would rather take all that money and stick somewhere earning interest and pay for what I may have to when I have to.

 

I just got the 6.7 and love it. I got plenty of warranty and am not worried...