Hi guys,

I'm hoping I'm posting this in the right place. I've been reading posts and blogs all over the net for hours on this topic but want to hear the expert advice I always get in this forum.

I'm headed out shopping this weekend. We're losing one kid from the household so I'm finally going to trade the '02 7.3 Ex w/250k for a newer CC p/u. In my area, I can get a 11-12 6.7 for 35k-45k, depending on options. In other words, I can find a low mile, plain jane 6.7 XLT CC w/cloth, etc. for around 35k and a fully loaded one for around 45k.

If I go with 6.4, I can move all the way back to a low-mile '08 fully loaded at around 30k.

Can those who have experience with both please weigh in? From what I've read so far, sounds like bone stock (DPF on, un-chipped, etc.) the 6.7 kicks the 6.4's butt in the MPG and drive-ability areas, especially with the 6sp vs the 5sp in the 6.4.

Any other thoughts?

 

That sounds about right. If you're looking for stock MPG and power, the 6.7 wins out. I believe the 6.4 still has the edge on aftermarket parts though.

 

Are you going to keep it stock? The 6.4 has a huge egr which just ain't healthy and is a big cause for the poor mpg. The 6.7 would be better if keeping stock I would say.

 

6.4 is a good hwy/towing motor. 1st generation with the DPF. No DEF..so the mpg's are worse.

I run about 13 where I live and about 17 on the hwy unloaded.

I think the 6.7 does better.

If you do alot of city driving then the 6.7 can deal with that better. The emissions for the 6.4 work best when good and hot.

 

Well, I would kind of like to keep it stock for two simple reasons. 1) For me, the quieter the truck the better. Noise on long drives makes me crazy. 2) Money $$$$. I looked at info on the DPF delete for the 6.4 and looks like I'd be into it for around $2k. That's not even adding an intake.

That being said, I really, really like the creature comforts associated with a Lariat trimmed truck. And if I went 6.7, I'm afraid the best I could do is an XLT. I haven't really done any negotiating so I'm not sure about that at this point. I'm just basing this off of price tags I'm seeing.

 

How would you primarily use the truck?

 

This would be a family vehicle replacing our Excursion. Kind of have to go with a p/u (which thrills me to death ) if we want to stay diesel. We tow a 8,500 TT around 6-7 times per year.

The truck would take a lot of 1 mile trips to the local school and 10 mile trips (one-way) to the grocery store. Basically, it would be a soccer-mom vehicle on my work days (I have a company vehicle).

 

6.7 or a gas motor would work better in your case I am afraid.

6.4 emissions would start to yell at you after a while.

 

Thanks for the input! Unfortunately that means I'll have to be a tough negotiator if I want the goodies !!

And on that note, I don't think I've seen any of the 2011+ trucks with leather and a 40/20/40 bench up front. Anyone seen one?

 

Yep I just looked at one the other day at the dealer that was a loaded lariat '13 model that had a split bench seat up front - even had nav. I'm not looking to buy, just curious what the '13's were like.

I have had my 6.7 for a couple years and it has been pretty good so far, aside from a replaced EGR and the module that controls the blinker wand. I don't do any towing with mine. I rarely do any short trips with it, my commute to work is 25 miles each way on mostly country roads with some stop/go in town driving. The majority of the time the regen cycles have time to burn through.

If it were me I would not use a diesel for short trips around town all the time. It isn't good for them, especially with all the new emissions equipment. As Senix said about the 6.4's - diesels in general like to run hot. The 6.7 even has an insulated header pipe that helps keep the EGT's up. When you are working it hard the system will passively regen, vs. the active regen where extra fuel is burned for the sole purpose of boosting EGT's to clean out the DPF.

The main reason short trips are bad for a modern diesel is two fold. 1 The short time does not allow the engine to get up to operating temps. 2 If the DPF fills and starts to regen the short trip will not allow the process to complete. When you put the truck in Park it kills the active regen process, but cutting it off mid-stream means it is not sufficiently cleaned out. The next time you start the truck it will wait until the temps get hot enough to start an effective active regen. If you are driving the truck short runs that means it may never get to the active regen state at all = your DPF will pack itself and you'll have to get it replaced.

 

You will get a "drive to clean" warning that doesn't go away until you drive till the regen is complete far before your filter will pack itself.

 

.........

 

If you're not trying to make major HP, you could just get a delete pipe, tuner, and run the factory exhuast.
I'm sure any muffler shop could add a muffler onto it if you wanted.
I have a 6.4, with 4" exhuast, and it's not loud.
The only time it's loud is if you get on the fuel really hard, but inside it stays quiet.

As said already, the 6.7 is better stock as far as using it as a car.

Even adding 2,000$ to the price of a 6.4 is going to be a lot cheaper than a 6.7, but it's all up to you bud.