[D K]

Hi guys

Been trying to get a straight answer between the 5.9 and 6.7 debate and keep on getting mixed views.

Are the 6.7's less reliable and economical than the 5.9's?
Will the 6.7 with a delete get similar mileage as a 5.9?

Seems that the newer engines have more problems than the older ones.


How are you guys with reliability as well as fuel economy?


David

 

[RWH]

6.7 + mild deletes + studs + common sense and good maintenance practices = reliability and good fuel economy.

 

[MoparProud]

And a stock 5.9=reliability and good economy.

 

[D K]

This is exactly what Im talking about...

But, good info none the less.

Any pointers as to some reading material into this obviously expensive hobby?

 

[MoparProud]

You're in the right place for reading material, as it's ALL OVER the forum!

Do some searching, then ask questions. There are bases covered from what transmission is better suited for what usage, to mileage, to power, to reliability...honestly you could probably spend a week straight reading.

Your end-use for the truck will be very helpful when asking for feedback; it helps us help you.:thumbsup:

 

[D K]

I have been lurking for a while, I must say...


The end use is light towing - 6000 lbs or so, basically a race car and a trailer. Not much.
Maybe some camping too, if I decide to later.

Bascally, my other car gets me pulled over too much because of the loud exhaust and a roll cage.
Its time....

David

 

[D K]

This site has basically gotten me to realize that there is a difference between the 59ers and the 6.7's.
Getting more info within each engine has been harder to find.

 

[Mudman1]

What are you going to be using the truck for? Location? Worried about interior comforts or no? Computers or no? Start there, in my opinion.

 

[D K]

What are you going to be using the truck for? Location? Worried about interior comforts or no? Computers or no? Start there, in my opinion.

I dont care if it has computers or not.
If the computers have proven reliable, then fine.

Interior comforts - yes, Id like to have as many as possible :drool2:


Purpose: light towing / daily driving
Location: Florida

 

[Jim W]

I have been lurking for a while, I must say...


The end use is light towing - 6000 lbs or so, basically a race car and a trailer. Not much.
Maybe some camping too, if I decide to later.

Bascally, my other car gets me pulled over too much because of the loud exhaust and a roll cage.
Its time....

David

David
First welcome to the forum.
Now what year of truck are you thinking about or have you bought one already?

If you are planning on buying a 2013.5 and up forget about deleting this truck. This year and up run with DEF and have a different ECM which is a 96 pin connector instead of the 72 pin connector that is on the 6.7L engines built from 07 and up to the 2012 MY.

Now if you buy an older truck 2007.5 to 2012 MY; you still might be able to delete the truck but delete programmers are getting hard to fine since the EPA has slapped some healthy fines on H & S and Edge products. I would recommend that you check out EFI Live for deleting possibilities for a truck built from 2007.5 and up to 2009. I do not know if anything is available for the 2010 and up to 2012 trucks, that is still on the market.

Jim W.

 

[D K]

Hello

Thanks for the advice.

No, I have not bought anything yet.
Went to buy an eco diesel but ended up walking out.

Glad I did because the extra fuel mileage gets wiped out real quick by the upfront cost.

Im a diesel mechanic on marine vessels (yachts) so I know some but not all.

Im trying to decide if a 2006/2007 5.9 might work for me, or maybe a 2008 to 2012 6.7?:confused013:

So, at this stage, I took the brave step moving from lurker to newbie - hoping to find whether a 5.9 or a 6.7 might work for me.

David

David
First welcome to the forum.
Now what year of truck are you thinking about or have you bought one already?

If you are planning on buying a 2013.5 and up forget about deleting this truck. This year and up run with DEF and have a different ECM which is a 96 pin connector instead of the 72 pin connector that is on the 6.7L engines built from 07 and up to the 2012 MY.

Now if you buy an older truck 2007.5 to 2012 MY; you still might be able to delete the truck but delete programmers are getting hard to fine since the EPA has slapped some healthy fines on H & S and Edge products. I would recommend that you check out EFI Live for deleting possibilities for a truck built from 2007.5 and up to 2009. I do not know if anything is available for the 2010 and up to 2012 trucks, that is still on the market.

Jim W.

 

[Mudman1]

^^^^He is on point. And mine comes "already better"...if you like a clutch.

 

[jlb27537]

Towing 6,000lbs, a hemi can do that. Any 5.9 or 6.7 can do that. The later trucks have more creature comforts and will drive/ride better, more car like.

The later years have more electronics on them and more emission restrictions on them. They all are reliable. The 6.7's will not get the fuel mileage the older 5.9's got. The more you move from stock, the more stress you are putting on stuff. Stuff will break....

You need to decide on creature comforts, how many gadgets you need/want, how much power, want to be legal/emissions???

I love my '12 3500 CC DRW. The way it drives, looks, features. Fuel economy sucks, but what do you want out of a truck that weighs 8,000lbs. I am almost always hooked up to a 16K trailer. It is not my daily driver, got a Honda for that.

 

[D K]

Thats exactly what im teying to find out: at what point do they become less reliable and at what point do they have the better ful economy?

I know I wnt be anywhere near the towing capacity.

What year did the ride get better?
What year did the comforts start to get better?

Where can I find out what each model year brung?

Or better yet, maybe someone can give me the cliffs notes?

David

Towing 6,000lbs, a hemi can do that. Any 5.9 or 6.7 can do that. The later trucks have more creature comforts and will drive/ride better, more car like.

The later years have more electronics on them and more emission restrictions on them. They all are reliable. The 6.7's will not get the fuel mileage the older 5.9's got. The more you move from stock, the more stress you are putting on stuff. Stuff will break....

You need to decide on creature comforts, how many gadgets you need/want, how much power, want to be legal/emissions???

I love my '12 3500 CC DRW. The way it drives, looks, features. Fuel economy sucks, but what do you want out of a truck that weighs 8,000lbs. I am almost always hooked up to a 16K trailer. It is not my daily driver, got a Honda for that.

 

[jlb27537]

Thats exactly what im teying to find out: at what point do they become less reliable and at what point do they have the better ful economy?

They all are reliable, The later years, the fuel economy went down due to more emission requirements.

I know I wnt be anywhere near the towing capacity.

What year did the ride get better?

Each body style change it got a bit more car like, a '12 rides better than a '08

What year did the comforts start to get better?

What is comfortable to you might be intolerable for me. You just need to decide on your budget, drive a few and go from there.

Where can I find out what each model year brung?

Or better yet, maybe someone can give me the cliffs notes?

David

David, I would suggest you figure out what you want to spend. A new loaded truck will be close to 60+K. A good used one a LOT less. There is not a year that was a bad year. Each generation is a step up in ride, comfort, towing capacity and usually a decrease in fuel economy due to emissions. The 5.9's will have a 4 speed auto, the 6.7's will have a 6 speed. The early 6.7's had 300/600 engines. The later 6.7's had 350/800 engines. Now the '13 and up have DEF and 370/850 engines.

Towing 6K, save a lot of money and just buy a hemi. The difference in gas vs diesel and the associated maintenance costs, you really do not need a diesel truck. NOW with that said, if YOU want a diesel truck, buy what you can afford.

 

[MoparProud]

^^^ Power ratings are off. No 6.7 had 300hp.

'07.5-early '11: 350hp/650lb-ft.
'11.5-'12: 350hp/800lb-ft.

Note those are automatic trans, '07.5-'12 manuals were 350hp/610lb-ft.

'13+ manual is 350hp/660lb-ft
13+ SO auto is 375hp/800lb-ft
13+ HO auto (3500 ONLY) is 385hp/850lb-ft (bumped to 865lb-ft for MY'15)

The best mileage for a Common Rail hands down, is an '03-early '04. This is not debatable.
Then the '04.5-'07 5.9 gets the next best mileage, followed closely by the '13+ trucks. Worst mileage is '07.5-'12.

From there....you need to go drive some trucks and see what you like, this is honestly not something you can describe over the internet; go drive different years from whatever model years you are interested in and see how the power is, how the truck drives, how it feels, how you feel about the interior appointments, etc.

The '10 and newer interiors are much nicer than the '09 and before interiors, although I have zero issues with either interior in my trucks.

 

[dundonrl]

And a stock 5.9=reliability and good economy.

newest 5.9 is 8 years old.. that's for a lot of people a huge downfall..

 

[southernend]

Don't let the mileage figures scare ya. I got around 16 with my 99 and I'm getting around 15 with my 12. It's not a big decrease like I was expecting. Comfort and handling there's no comparison. And for what they want for a 06-07 is just crazy imo. For a couple thousand more you can be in a 10-12 and possibly still have a warranty. Power wise my 12 would absolutely have stomped my 99. The back seat room is huge compared to a 3 rd gen and honestly that's why I skipped over the 3rd gens. Good luck.

 

[D K]

Thanks guys.

Now I feel like Im getting somewhere....arty018:

Gasoline powered vehicle is out.
For many reasons, the least being that I have the ability to get diesel cheaper arty018:

My budget is around 25K. I could go higher if I financed, but anything near 20-25k I could buy outright.

Also, it is my understanding that the 08's had a 5.9 with a 6spd automatic.

Im looking for a 2wd crew (or quad) cab.

D

^^^ Power ratings are off. No 6.7 had 300hp.

'07.5-early '11: 350hp/650lb-ft.
'11.5-'12: 350hp/800lb-ft.

Note those are automatic trans, '07.5-'12 manuals were 350hp/610lb-ft.

'13+ manual is 350hp/660lb-ft
13+ SO auto is 375hp/800lb-ft
13+ HO auto (3500 ONLY) is 385hp/850lb-ft (bumped to 865lb-ft for MY'15)

The best mileage for a Common Rail hands down, is an '03-early '04. This is not debatable.
Then the '04.5-'07 5.9 gets the next best mileage, followed closely by the '13+ trucks. Worst mileage is '07.5-'12.

From there....you need to go drive some trucks and see what you like, this is honestly not something you can describe over the internet; go drive different years from whatever model years you are interested in and see how the power is, how the truck drives, how it feels, how you feel about the interior appointments, etc.

The '10 and newer interiors are much nicer than the '09 and before interiors, although I have zero issues with either interior in my trucks.

 

[MoparProud]

There has never been a 5.9 with a 6 speed auto. ALL '08's and newer are 6.7.

'07 can have either the 5.9 4 speed auto, or the 6.7 with the 6 speed auto.