2007 5.9 Cummins (87k miles) vs 2021 6.7 Cummins (150k miles) — Which Would You Buy and Why?

[Rafa2708]

Looking for opinions from people who have owned both a 5.9 and a newer 6.7 Cummins.


I’m currently trying to decide between two trucks for what will be a long-term build.


Option 1:
2007 Ram 2500 4x4 8ft bed
5.9 Cummins
87,000 original miles
One-owner Florida truck
Minor sideswipe accident reported years ago
Looks very clean and mostly stock NO RUST


Option 2:
2021 Ram 2500 4x4
6.7 Cummins
150,000 miles
Much newer truck with more power, comfort, technology, towing capability, and a better transmission


The intended use is probably where this gets interesting.


This won’t just be a daily driver. The truck will be used as:

• Work truck for a handyman/property maintenance business
• Cross-country travel vehicle
• Mobile office
• Future overland/camper build
• Long-term ownership (10+ years if possible)

My thought process is this:


The 2021 is objectively the nicer truck. Better interior, better ride, more power, more modern everything.


But the 2007 has significantly lower miles, the legendary 5.9 Cummins, fewer emissions systems, less complexity, and costs roughly $14,000 less.


The money saved on the purchase could go toward a full Carli suspension system, camper setup, Starlink, solar, storage, and building the truck into exactly what I want.


For those of you who have owned both generations:

1. Which truck would you choose and why?
2. Is a clean 87k-mile 5.9 worth giving up the comfort and technology of a 2021?
3. How much does the 150k mileage on the 2021 concern you?
4. If your goal was to build the ultimate work truck + travel truck + overland platform, which one would be your starting point?

Looking forward to hearing from people who have actually lived with both trucks.

 

[06 Dodge]

If you can live without all the new tech the 2021 has, in the long term the 5.9 is a better option IMHO and it being an 07 means it was among some of the last 5.9 Cummins installed in a Ram truck, I had the 5.9 on in my 2006 and when needed it got great mpg so long as I kept it at or under 70 mph, what's nice about the 5.9 it has no costly Def, DPF or stupid emissions junk, it can run on 5%-10% Biodiesel without any problems and at just 87K on the engine its barely broke in meaning it has lots of life left in it, I would check to be sure it was well maintained with regular Oil Change Intervals, myself the best 2 oil filters to use are either the Donaldson DBL 7340 (I use this filter on my current 2022 Cummins and used it on my old 5.9) or the Fleetguard Starapor 16035.... Oh as for the trans if it does go out its cheaper to rebuild and it can be easily be built stronger then stock and cheaper too.

 

[Burla]

That's not even a hard question, I think 2007 was last year or close for the famously popular HO Rams. High pressure system with the cp3 pump. Usually if something happened to those trucks it was in fuel system (pump or injectors) or transmission, not like new isht that anything can break at anytime. We had 3 of those HO Rams in the family, I had one. Man if you knew what it was like when those engines first came out, they were so popular legitimately so.

Now you have DEF, who would want that? Plus Cummins got EGR and DPF I think 2007.5, so if you don't have those items freak'n heahzus man, are you kidding me, plus 14k cheaper? You need to know it is is a 2007 or 2007.5 which makes it even more of a slam gunk if it was true 2007.

 

[Burla]

So yeah if you are sure it has the 5,9, it doesn't have particulate filter, DEF, but does have EGR cooler in cylinder type. But I think it was not anything like the 2007.5 EGR cooler and VGT which are wildly complicated crap that ruined the Cummins name. For sure your 2021 has that cr@p.

 

[06 Dodge]

So yeah if you are sure it has the 5,9, it doesn't have particulate filter, DEF, but does have EGR cooler in cylinder type. But I think it was not anything like the 2007.5 EGR cooler and VGT which are wildly complicated crap that ruined the Cummins name. For sure your 2021 has that cr@p.

The 2007 5.9 is the same as the 2006 5.9 the difference is it will have a build date before Jan 01 2007, I was told anything built on or after Jan 01 2007 had the first of the 6.7 Cummins with the crappy EGR but then the egr could be blocked off

 

[JayLeonard]

I would choose the 07 with the 5.9.
I have a 21 and love it, it tows great and I like the technology. BUT my son has a 05 and it lacks nothing in the way of power. Even before the tuner and twin turbos it was strong. ( now he can kick a Mustangs a$$)
And the 07 is pre def

 

[CanuckRam1313]

For your intended purposes.. I'd go with the 5.9 common rail Cummins, hands down!!!!

So much potential for engine upgrades and ease of use, too!