Is there any difference in the ride/smoothness? I drove the 6.7 and it was smooth...how does the 5.9 compare?

 

Well, the 5.9L will have the 4 speed auto and the 6.7L will have the 6 speed auto, so the 6.7L may drive a little smother (not sure though, I'm a manual guy).

As far as engines go, they both have pro's and con's, but most will say tostick with the 5.9L if you can still find one.

 

I just got back from doing 1500 miles in my cousins 6.7 mega cab and I didn't think it was no quieter inside at speedthan my 5.9, even though at 75 his engine wasdoing 1850 RPMwere I would be doing 2150 RPMand I get better fuel mileage, mine was smother but that could be from being a 3500 dually with full air on a light load, dam thing was rough on SC's roads.

I don't know if the duallyhad anything to do with the badmileage, now we three guys would have been cramped in my truck,Quad cab, but we would have used less fuel in my truck, plus in parts of thesouth you have to look for ULSD, were I can use either

 

I personally would go with a 5.9.... especially if you are looking to do performance mods... the 6.7 i think is a little quieter and stuff and if you plan on keeping it fairly stock its a great choice!

herb... the dually might have messed with the mileage a little bit but is he still breakin in???

 

i was told you cannot/should not let the new 6.7s idle much...bad for them. True?
5.9 seems like gets better mileage, less issues????

 

Because of the DPF's you don't want to let a 6.7 sit and idle for hours if you don't do highway miles. If you idle A LOT and only do short runs it will be less likely to go into regen.

As long as you take it and run it at highway speeds it will re-gen fine.

Comparing the 6.7 (we had) & the 5.9 we have is like compairing apples & grapes....the 6.7 was a stick & the 5.9 is an auto. The 6.7 had plenty of power; but it sucked on milage.

 

I've drove um both and the 6.7 ride a lil smoother and the 6 speed tranny is sweet

 

My Father has a 2007 6.7L and I have a 2006 5.9L. Both are quad cab, 2500, auto's and 4x4. I don't know why his rides smoother but I feel itdoes. It isn't a huge difference, but the drive/ride/smoothness is improved on his. I told him after I do my front end suspension/leveling we will see who has the smoother ride. It doesn't bother me, because it is just me in my truck and he gets to listen to Mom go uufffgghhh on the big bumps. Ride/smoothness I feel is subjective and individual, so if you can drive both that will help you make up your own mind.

 

Mine isn't smooth unless I have a lot on it.