Is the fuel delivery system on the 6.7 engines different than on the 5.9 engines?

I'm just wondering, since we're all running ULSD now, if the 6.7 is better equipped at handling the new fuel. Will the engine life of a 6.7 running ULSD be better than a 5.9 running ULSD?

I'm wanting to buy a new truck very soon and I'm leaning very heavily towards an 07 5.9 but I will wait if the new engine is going to handle this new fuel better. And I'm talking strictly the fuel system... I know all about the other new emissions stuff.

 

?????????? Dont really know???? I would have to say that since the new Fuel Systems are designed around the ULSD then they would be more compatible to the fuel than the 5.9! BUT- - - - -we are not talking about having to have special injectors, lines, gaskets, heaters//exc..........so...........do yourself a favor and get a PROVEN 5.9l Cummins and forget about all the emissions junk that is coming out. Good Luck!

 

The Dodge literature that I read said that "higher fuel injection pressures-an increase of 2900 psi over the previous common rail system" also "the fuel filter offers higher efficiency-with the capability to handle ultra-low suler fuel."

 

Yeah the new engines ARE designed entirely around the new fuel and they produce the advertised power out of ULSD while there is a very slight drop off with the 5.9's using ULSD. But it's not noticeable. Gotta agree with getting a proven 5.9. Not that I think the 6.7 is or will be bad but simply because you can do so much more to a 5.9 in the here and now.

 

I will almost bet my life on the fact that the aftermarket will create new products for the 6.7 that will get rid of the restrictive EGR system. Of course it will be deemed "OFF ROAD ONLY" but it will come. And when it does, watch out 5.9 cause there is no replacement for displacement!

 

We have three of the 6.7's running in our service fleet, and there are two issues we ran into right away. The first is that they have to be operated with a load or they end up with particulate filter error codes and going back to the dealer to get them to cycle them through the burn sequence to clear the filter so it will run. The second, and biggest to us, is the fuel mileage is really low. We are lucky to get 12 mpg on the highway, and average around 7 and none of it is in town. Our older third gen Dodge diesels ran in the high teens as an average, so this really stinks.