Info on modern Ram 6.7 Cummins

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Been casually truck shopping for a while now, very careful/not in a rush to buy.

One of the trucks I'm looking at are Ram 6.4's but the 6.7 keeps popping up, often for a similar price to the 6.4. I've always had it in my mind to avoid diesel but wanted any feedback that you all may have. I would be looking at primarily 23/24 Big Horn models that are certified.

I've heard that the CP4 was an issue a few years ago, some engine failures around '22. Other than that, good engines with all the emission stuff these days?
 
Ram CP4 years were 2019 and 2020. For 2023/24 it is not a concern.

The skepticism for 2019-2024 is the CGI (compacted graphite) block design and the hydraulic lifter issues. Supposedly the CGI block does not take well to additional power. There were some 68rfe improvements for 2019+ that may or may not matter to you depending on your application.

If price is comparable between 6.4 and 6.7 trucks, the 6.4 candidates are overpriced. A 6.4 might not be expected to go as long without overhaul (my impression is that they get super clattery with miles), the 2019+ 6.7 will always be suspect of cam issues and emissions system needing attention. Depending on your use case, warranty, and how long you plan to keep it, this may not matter to you. A lot of these discussions center around a purely financial basis, projecting gloom and doom around diesel reliability, assuming four-five figures every hiccup. Only you can decide how much the bottom line matters. Your ability to DIY the maintenance/upkeep/repairs will matter bigly.

We tow a camper with our 2014, 3500 megacab...which shares much with rams up to 2024. Overall our rig is 58 feet long. Diesel refueling at giant truck stop lanes when underway is one of the practical reasons why diesel makes more sense than gas for some applications.
 
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Have to agree with jeepman: if you don't do heavy towing or hauling, I don't think it's worth the extra hassle of worrying about DEF, DPF, all manner of EGR issues and other emissions bugaboos. Keep it simple and you'll have less stress.
 
I daily drive a 24 6.7 mega cab 2500 laramie. I purchased it new and had it shipped from Louisiana. I had 2 transfer case output seal failures, and the transfer case itself had to be removed and resealed under warranty. I have an odd ticking sound, at high idle, which is audible in the right front. Many report this as normal, as did the dealer; however, I don’t believe it’s normal because it never did it until about 9k miles. I love the truck, it has tons of power, gets great highway mpg, and the interior is incredibly comfortable and spacious. I work in healthcare and did not need a diesel; I just wanted one. Only time will time if I keep it long term but as of right now, aside from the warranty issues and having no local dealer loyalty (which is not ideal at times), I love the truck. I have not had any emissions related issues in the 11,200 miles I’ve owned it. Hope this gives you a real world perspective from someone who doesn’t hot shot or use the truck for business purposes.
 
Thanks for the replies so far; solidifying what my gut is telling me. Probably will steer clear of the 6.7 if I decide to go Ram.
 
Never owned a Cummins & only Power Stroke's but what has been mentioned is sound advice. I haul a 4,300 lb slide in truck camper in the bed of my F-350 & most of the dually's of that day were 6.0L diesel's. Not impossible to find a V10 but I thought I wanted to have enough power Incase I went to a 5th wheel RV. One must really consider what they are going to need it for & if the gobs of power aren't necessary then a 6.4L should suffice. I'm assuming since you're considering gasoline that it would be a SRW Ram? I don't know if they offered that engine in a dual rear wheel. I'm sure they are nice to look at. You look like you're in an area that would be ripe for used vehicles (little to no salt). Have you considered used either way with an aftermarket warranty of sorts?
 
As stated a few times now, don't get the diesel unless you need it, its not worth the extra expenses if not.

That said, the 6.4 should be substantially cheaper than the 6.7 with all things being the same.
 
I have a '17 RAM Dually with the HO Cummins, Aisin transmission, CP3 HPFP, 4.10 gearing. It towed a few large, heavy 5th wheels for most of the time I've had it. These days it plows the driveway, and makes trips to the grocery store. No issues to report. It's been a great truck. This was before they went to hydraulic roller lifters, the CP4 ('19-'20) or the CGI block. I have random people occasionally ask if it's for sale, because it pre-dates the years with the valve train, HPFP, or block issues. 2018 would be the last year before the 'problem' years.
 
Never owned a Cummins & only Power Stroke's but what has been mentioned is sound advice. I haul a 4,300 lb slide in truck camper in the bed of my F-350 & most of the dually's of that day were 6.0L diesel's. Not impossible to find a V10 but I thought I wanted to have enough power Incase I went to a 5th wheel RV. One must really consider what they are going to need it for & if the gobs of power aren't necessary then a 6.4L should suffice. I'm assuming since you're considering gasoline that it would be a SRW Ram? I don't know if they offered that engine in a dual rear wheel. I'm sure they are nice to look at. You look like you're in an area that would be ripe for used vehicles (little to no salt). Have you considered used either way with an aftermarket warranty of sorts?
Thanks for the comments. I would be looking SRW, our future needs wouldn't exceed those capabilities. This area is easy on vehicles for the most part, so yes very good options out there. I would definitely consider a warranty if the truck isn't certified, just for the peace of mind.
 
As stated a few times now, don't get the diesel unless you need it, its not worth the extra expenses if not.

That said, the 6.4 should be substantially cheaper than the 6.7 with all things being the same.

It's odd; I've only seen a 2-3k difference in price on average with the trim level being equal.
 
Thanks for the comments. I would be looking SRW, our future needs wouldn't exceed those capabilities. This area is easy on vehicles for the most part, so yes very good options out there. I would definitely consider a warranty if the truck isn't certified, just for the peace of mind.
It sounds like you're a very good candidate for getting the gasoline engine (new or used). There is absolutely no benefit going with Diesel for "fuel savings", not that you've implied that. Diesel tech has gotten quite expensive for repairs & maintenance. You'd need to find a shop willing to work on diesels. This all does peek one's interest of "Which One" but overall the diesel will be more costly if something goes bad. Hope you find exactly what you want.
 
It sounds like you're a very good candidate for getting the gasoline engine (new or used). There is absolutely no benefit going with Diesel for "fuel savings", not that you've implied that. Diesel tech has gotten quite expensive for repairs & maintenance. You'd need to find a shop willing to work on diesels. This all does peek one's interest of "Which One" but overall the diesel will be more costly if something goes bad. Hope you find exactly what you want.

You're absolutely right on the lack of need for diesel. I also do my own servicing which is a lot more involved on the diesel. Thank you sir! I'm even looking at Tradesman models with packages, honestly not bad. Only upgrade I would make is a larger android radio.
 
It pains me to say it, but diesel does not make sense for most users. Back when diesel fuel was cheap, emissions less stringent (and MPG was higher), and the diesels superbly reliably and durable, diesel made a lot of sense even for grocery-grabbing non-haulers like me.

I had a 2002 Ram with the 5.9 and 6 speed. When I bought the truck, diesel fuel was $1.55 a gallon, I could get 20mpg highway with a 6800# truck, and it was superbly durable and reliable (even as a VP44 truck, IYKYK). I paid < $32k brand new for the truck.

But today, with even "cheap" fuel nearly $4/gallon, The diesel trucks STARTING at nearly 60k, the mpg being significantly worse and the true cost of ownership of a diesel being much, much higher, how does diesel make any sense for anyone not burning gobs of fuel?

The reality is that the supposedly lower cost of ownership of a diesel in fuel savings can be entirely wiped out for a decade or so with a single major repair event. You lose your aftertreatment? Pop a turbo or wipe a cam? If so, your fuel savings of buying diesel instead of gasoline are gone for nearly a decade.


A diesel buyer today is signing up to either burn 8000-10,000 gallons of fuel a year or to never break even at all on ownership cost.

If I ever own another diesel, it will likely be a very old entirely mechanical engine with zero electronic controls whatsoever. Think K19 or 6BTA5.9 and you're in the ballpark.
 
As stated many times, the diesel is great, but not worth the hassle unless its working hard. And that what's needed to keep them working well. The diesels need to pull heavy, for distance to keep the emission system clean. Short trips and idling will cause a multitude of problems.

Seems like the gas trucks are doing a bit better in fuel mileage than years ago. My F250 will eek out 18mpg on the highway if I'm careful. My father's new F350 will do that even with his lead foot.
 
As stated many times, the diesel is great, but not worth the hassle unless its working hard. And that what's needed to keep them working well. The diesels need to pull heavy, for distance to keep the emission system clean. Short trips and idling will cause a multitude of problems.

Seems like the gas trucks are doing a bit better in fuel mileage than years ago. My F250 will eek out 18mpg on the highway if I'm careful. My father's new F350 will do that even with his lead foot.
The better-than-ever MPG of the gasoline options is really the nail in the coffin for diesel trucks for general light-duty pickup use.

I remember the first time I rented a hemi Ram with the 8 speed TF8. 25mpg with the bed full of mattresses and dragging air at 80mph. That's when I knew the game was changed seemingly forever.


No amount of transmission wizardry will get your modern "big 3" diesel to 25mpg.

Even a very crude cost analysis of cost to buy, cost to own, and cost to maintain will have the diesel come out as 2nd best. Which is sad, because we have the tech now in modern diesel fuel systems to do incredible things. The tech exists to make a modern diesel that would get 25mpg highway. Heck, the tech exists to make a diesel electric hybrid truck that would have 1000 lb-ft and get 30mpg + around down in a 3/4 ton 4x4.

Like that super-affordable barebone Toyota truck that will never come to the usa, the tech and market is there. The freedom is the only thing missing.
 
But today, with even "cheap" fuel nearly $4/gallon, The diesel trucks STARTING at nearly 60k, the mpg being significantly worse and the true cost of ownership of a diesel being much, much higher, how does diesel make any sense for anyone not burning gobs of fuel?

The reality is that the supposedly lower cost of ownership of a diesel in fuel savings can be entirely wiped out for a decade or so with a single major repair event. You lose your aftertreatment? Pop a turbo or wipe a cam? If so, your fuel savings of buying diesel instead of gasoline are gone for nearly a decade.
Sometimes vehicle ownership it isn't purely about the $$ bottom line. @6.7 CTD is in the same boat. He doesn't really need the diesel but he likes the truck for...reasons. Sometimes it's just $$ spent on a hobby.

Our 2014 Cummins, Megacab 3500 SRW...

Get a free TSD fleet card or use other discounts and our truck has been running on $2.60 to $3.20 fuel since last summer. I buy DEF at the pump locally for $3.75 and I get about 1000 mpg, so that's a noise in the data. The truck will get 20mpg on interstate cruises depite weighing 8500 pounds with me in the drivers seat. The additional maintenance vs gas involves fuel filters ($100 every 15k miles) and big/expensive oil changes. With rebate synthetic oil and the best filter I can buy (Fleetguard Stratopore or Donaldson)...my oil changes are $50-55.

The truck maintenance and upgrades became a hobby for me on our last truck, so my labor is free and it gives me something to do. I do lots (excessive) of PM since we travel far out of town with it. Shopping for deals on parts is part of the hobby.

Tires, suspension parts, and brakes are the same as a gas truck. Other parts aren't that bad despite my tendency to by fancy/OE parts. Cummins water pump was $56. (I think a 6.4 water pump is >$200.) $30 gates fleetrunner belt. Fancy big rig coolant was $50. Continental upper radiator hose was $20. Mopar lower was $50 (two hoses). Fleetguard air filter, $30. I carry a spare DEF injector ($100), water pump ($56), transmission thermostat ($30), my old belt, and set of fuel filters in the camper/truck. Expensive things like CP3, injectors, or DPF get covered under warranty or amortized across many miles. It only has 82k on the odometer so anticipate those items to be far out. Our truck got a turbo actuator right before we purchased it so fingers crossed not needing to do that again. Yeah, the first EGR cooler, NOx sensor, or DEF pump/heater module will sting if/when it happens.

My last truck had 320k on the factory head gaskets, injectors, and CP3. I suspect the turbo had been replaced. We nursed the slippy torque converter for years. I had the transmission upgraded/rebuilt ($6k) and we lost it in a crash two months later, but that $1700 upgraded Goerend low stall torque converter was awesome while it lasted.

Beyond maintenance/repairs, the truck itself is more expensive and breakdowns are a larger $$ liability, but the extra power, range (55 gallon tank), and extra space to maneuver at truck stops makes travel days easier. It is not my daily driver. For me, the truck provides our family vacations and the additional $$ to reduce my stress while towing so the money spent is a luxury. It's quieter and the family doesn't get uneasy everytime we power up a hill in 2nd gear at 4500 RPM. Granted, a smaller camper would do the same...

If we had gotten a gas truck, I'd add a 15 gallon saddle tank in the bed and try to limit fuel stops on tow days. The transmission would shift more often and I'd be slower on the hills but I'm sure we'd get to the campgrounds just fine.

and I can drain a little fuel from the filter into a dixie cup when it's time to start a campfire...
 
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