Any 6.4 Powerstroke or 6.7 Cummins owners? Input requested

My Uhaul tow pig is simply too long for my new RV.  When I initially bought it, I had a 26' RV and now I have a 36'.  Those of you who saw the picture I posted saw how loooong it was... about 72'.  Just not practical, and probably not legal.  So the Uhaul will go (anyone want it, GRM discount) and I'm going to go the conventional pickup route.  My trailer weighs 8650 lbs dry.

I've got a few trucks I'm looking at.  One is the 6.4 Powerstroke F250 from the late 00's.  I can get one that's been "bulletproofed" with supporting documentation for $8-$10k.  They typically have 150-250k miles for that price range.  From what I can see they are rated to tow 12,500 lbs.  I also came across this 2017 Dodge 3500 Cummins.  I've spoken to the owner and he used it as a hotshot for the past 3 years averaging 90k/year.  He said no major maintenance needed, just water pump, fuel pump and routine oil/fuel filter changes.  He has provided proof.  It's got 400k miles.  I can get it for $12,500.  It's towing capacity is insane.

Anyone here own either of these?  Experience in reliability, towing and fuel mileage?  I am going to avoid the 6.7 Powerstroke like the plague.  I dealt with them at work for 10+ years so I know better.  Haven't seen any Duramax of interest.

Input on those two options wanted.  Less money for older bulletproof Powerstroke or more money for newer high mileage Cummins? 

Cummins all day, every day, twice on Sunday.

Years ago had a friend that was a Ford master tech, he absolutely refused to work on the 6.4L. 

In reply to calteg :

same. When i was truck shopping my uncle - lifelong diesel mechanic and parts guy - said buy the cummins and put up with the Chrysler around it.

I have seen several 600k+ mile 16+ rams, the last one was at a dealer looking for $28k. My 2016 is around 104k and tows everything 

The 6.4 is what you should be avoiding like the plague. I'd only buy one if I was sending the engine to get redone by a handful of powerstroke rebuilders. 

The Cummins seems like a good deal in the low teens. A lot of truck for the money, even at that mileage. 

Ford Diesels

7.3 (OBS, Superduty to early 2003)  - Relatively low power, relatively simple to work on, no EGR, DEF, or other silliness.  Compared to a modern diesel they are pretty old, slow, and crappy.

6.0 (Superduty late 03-07) - Make good power and run like a modern diesel but have a reputation for being a bit troublesome.  EGR and VGT turbos but no DEF.  Some people absolutely love them.  Not particularly hard to work on and most of the fixes are well documented at this point.  HUUUUGE aftermarket.  

6.4 (Superduty 08-10) - Gussied up 6.0 with twin turbos and DEF, EGR, DPF, etc.  Even 6.0 guys hate them.  So bad Ford quick buying Navistar diesels and went to their own internal design with the 6.7

6.7 (Superduty 11+) - Good engine with good reputation, have DEF and EGR and all that fun stuff.  I am not well versed on the different years of the 6.7 but they all seem to have a solid reputation.  Personal preference for me would be a 2016+ with the aluminum body, often called the "alumaduty"

In reply to 93gsxturbo :

Thanks!  The 6.7 Powerstroke uses the Bosch CP4 fuel pump.  It's not a matter of if it disintegrates just a matter of when.  It then sends metal shards everywhere.  Repair is about $20k.  Seen it literally at least 500 times. 

Saw a Dodge at the 24 with a 900k mile Cummins club badge.  Wouldn't expect to see that on a Powerstroke or Duramax.  

I've got a 2015 RAM 3500 with the 6.7l.  It's only got a little over 100k miles on it but I've been very happy with it.  I did have to replace the turbo actuator and a front wheel bearing in the 60k + miles that I've owned it both of those parts gave me plenty of warning that they needed attention.

The only thing I don't particularly care for about it is the fuel mileage.  It's pretty abysmal.  I get a best 13 MPG empty and as low as 9MPG pulling a 13k lb enclosed gooseneck.  I get around 10 MPG pulling my 8k lb 24' enclosed car trailer.  To be fair most of the time I drive with the cruise control set at 82 MPH.

I'm going to go a different way.  If we were comparing the 5.9 Cummins, yes.  The 6.7L is great, but still has all the extra external failure points, which is what will fail on either one.  A properly bulletproofed 6.4L with half the mileage for the same price range?  Further evidence of the Cummins fanboi tax.  Lots of people LOVE their Cummins, and there is a ton of great stuff about them.

Either one will have three times the torque you need to tow
Either one will be better than gas MPG
IMO, the dodge truck that was built around the Cummins is a nightmare.  Terrible materials and build quality, quicker to rust, and don't even get me started on the 68RFE transmission.  When it goes, it won't need a rebuild because the clutches wore out, it will need sprags, a new valve body, and you'll be very lucky if the valve body hasn't caused a crack in the case.  $4000 MINIMUM for a build on someone's bench.  The fact that this one hasn't needed to be remaned twice is a miracle, or maybe it has and the seller isn't disclosing it.  Dodge took a rattly inline 6 diesel and put a transmission behind it that is basically a 727/A518 that has been continually band-aided since 1985.  The 5R110 in the Ford, however, has line pressures that tend to be lower than some tow-folk like, which is easily fixed with a $60 kit and an hour.  My years running transmission repair shops has me a little on a soapbox about transmissions... things that many people overlook.

Familiarize yourself with B10 and B50 life expectancy.  They are mileage numbers that correspond to relative lifespan at which 10% and 50% of diesel engines require a major overhaul.  These are not subjective, they are reported data from millions of engines.  The B50 lifespan (that is to say that 50% of a certain engine in a production has needed a major overhaul) for the 6.4L Stroke is 375,000.  The B50 life of a 6.7L Cummins is 250,000.   That Cummins is fast approaching almost double of its life expectancy based on the average.  Buying that Cummins is like adopting a 17-year-old dog with cancer and one leg.

The 6.4L however is tucked inside one of the best-built, better quality, better assembly vehicles I have ever owned.  When I would go from my F250 to a 6.7L Ram at work, it was like going from an Escalade to a 1975 IH Scout.  Buzzes, rattles, squeaks, vibrations, punishing ride, torn seats at 80k, and good lord you practically had to take off your seatbelt to reach the radio or the cup holders.  They have become much better in the later years, but still they're a big plastic rattlebox.

I realize that truck and diesel opinions are like buttholes.  Every one has one and they all stink.  I'm not brand loyal by any means.  I've owned them all, and worked for a utility company in maintenance where we had four brands of truck, gas, and diesel.  The only ones I've consistently regretted were the Rams.

If you find a good Cummins and you like it, go for it.  In all honesty, maybe you're the type of person who prefers max towing capacity and you'll sacrifice some other amenities.  No judgement.  I'm speaking for myself here.  Just please don't drink the Cummins Kool Aid.  You'll overpay and get a great engine with a glass transmission and less "truck" for your money.  Even the venerable 5.9L was wonderful, but the fanbois made them so expensive that it wasn't worth the buy-in back in the 90s and 2000s

I've had a 6.7 Cummins since 2010. It averages 10-12 mpg when towing an 11k 28' trailer at 75-80 mph and doesn't complain a bit. Without the trailer, it's about 18 mpg. It's an early 6.7 so it's not one of the mega-tork models, I think it's 350 hp and 600 lb, the manuals were slightly derated compared to the autos.

The truck has right about 100k on it and has needed no unscheduled attention other than a failed dual mass flywheel and a PS line that extruded its teflon liner - the latter was an easy fix with parts on the shelf at NAPA. I also had a leaking front seal that was fixed by replacing the crankcase filter.

No rattles or squeaks, the interior looks brand news. The 2010 is a lot nicer inside than my FIL's 2006, although his 5.9 is a sportier feeling engine with sharper response. It's tuned, though. I did swap out the stock shocks for remote reservoir Foxes a few years back because the stockers felt worn out to me, and the Foxes were a definite upgrade. Rides better with a trailer on the back, of course.

Either 6.7. I wouldn't touch a 6.0/6.4. But of course I'd convert to cp3.

So the bulletproofing of the 6.4 still leaves it a E36 M3 pile? 

I don't have experience with either, but watch videos on both as I want one for towing someday soon.

I like the Cummins as they seem to be easier to work on compared to newer trucks. One thing that always comes up is the heater grid bolt. If I got one I would immediately put a banks monster ram intake to fix the issue. Banks has some really informative videos on it.

Also hear a lot about fords and the cp4 pump failing, but not sure if that's on newer models than your looking at.

SKJSS (formerly Klayfish) said:

So the bulletproofing of the 6.4 still leaves it a E36 M3 pile? 

Yes.

There is no such thing as a "bulletproofing". Consider it more "$10k worth of unscheduled maintenance that requires me to replace every gosh darn part in the top end and fuel system of the motor, netting me a life expectancy measured from weeks to years".  They were the first attempt at a High Pressure Common Rail injection, the first attempt at compound turbos, the first attempt at DEF, etc in a Ford chassis. 

6.4 parts are also getting a bit thin on the ground because they were only were built for 2 years and are such piles that no one rebuilds them.  Then consider they are (personal opinion) put into one of the ugliest trucks Ford has made in a long time and you have a real stinker on your hands.  

The other thing that stinks is that if you *buy* a 6.4 and maybe it turns out to not be a turd, you still can't ever sell it because of the reputation, regardless of how good your example may be.  

I wouldn't buy a used up 400k mile hotshot Cummins either because I am not an idiot, but given the two options, that's the better pick.  

Hotshot guys make their numbers by getting something from A to B as economically as possible.  While they don't want breakdowns any more than the next guy, the bulk of their maintenance is all going to be done as economically as possible and there will be tons of little things busted up on those trucks.  This one is prime example.  The dented bumper and cracked light doesn't make you any more money, so its not getting fixed.  Rear windows that don't roll down?  Doesn't make you any money, not getting fixed.  Radio with only 1 speaker working?  Doesn't make you any money, not getting fixed.

The trucks you want are the ones that Grandpa lovingly wiped with a diaper in between his weekly trips to church and the liquor store, or at least trucks that someone took a bit of pride of ownership in.  

If you just want something to yank stuff, a rig like this would get my money any day of the week and twice on Sundays.

https://www.cars.com/vehicledetail/ab12a93a-1a87-46e1-ac4d-0c6727524911/

Thanks!  Yeah, I know an engine can't be perfect, I was just using the term they use to "fix" the big know issue with the 6.0 and 6.4.   The CP4 in the 6.7 is horrendous when it lets go. 

It's common knowledge that the 6.4 (MaxxForce in IH parlance) is a turd.  But if you can make it stay together, and a few have, that engine will best all challengers in the power wars.  All of them.  It can make  REDONKULOUS power.  Look at the rods it uses.  It makes even the 6.7 PS rods look puny by comparison.

But I'd avoid it unless I was a sled puller or drag racer.

Keith's post reminded me that I put Fox shocks (based on his recommendation) on my truck as well.  Replacing shocks at 100k miles is pretty much routine maintenance as far as I'm concerned but they would have been a worthwhile upgrade before they got tired..  I'm pretty sure I put front brake pads on when I did the wheel bearings.

The concern with using the term "bulletproofing" is that there is no guarantee that a bulletproofed truck is going to be any better or worse than a stock rebuild or a factory, never-opened-up engine.  While there are certain things that are definitely worth doing on a 6.0/6.4 (studded, EGR/CAT delete), it gets pretty murky from there on a properly functioning, non-hotrodded engine.  Did the rebuilder use OEM Navistar O-Rings, or cheapo depot ones?  What head gaskets were used?  Are they any better or any worse than what was in there from the factory that lasted 200k miles before letting loose? 

There is also the issue of parts availability on these 15 year old engines.  Some stuff, like the OEM USA Made oil cooler for the 6.0 Powerstoke, is straight up unavailable.  Sure you can get aftermarket ones, but even the new-in-box Ford ones are now made overseas.  The market is littered with crappy parts too, like knockoff injection contol pressure regulators in Motorcraft boxes.  While parts availability is an issue with most makes and models to a point, it is compounded on these machines by being owned by 2nd or 3rd owners that may not have the budget to buy top-tier parts, the demand for parts, and the generally accepted knowledge that with notable exceptions, the only parts worth installing are the OEM parts.

Why was it bulletproofed has as much of a play as to who did the work and what parts were installed.  Did Timmy Teenager buy grandpa's truck, throw an SCT Stage Eleventeen tooner on it and then drive it over the rockies with their toes tickling the radiator fan?  Did someone not monitor the deltas and cook a head gasket or burn up a piston?    

will add that I have a tuner and deleted the broken things on my cummins and I now get 25-26mpg empty highway and 21-22 highway with an open trailer and any vehicle on it, and i got 16-17 with my 28' enclosed trailer. in situations where i'm doing zero highway driving i get 19-20. I do not drive 80 with a trailer, I tend to go a few over the limit. pushing a brick towing a bigger brick through the air at 82mph is asking for E36 M3ty mileage. i run the calibration that gives me the best efficiency and don't crank it up to go fast because it's a 3.5 ton truck. the tuner gave me 3-4mpg bump across the board. 

I'm a fan of the Cummins engine. Being an inline 6 vs a V8, it's much easier to work on and there are fewer repairs that require cab removal to perform.

I have a 2015 Ram 3500 with around 210k miles. Bought it used a few years ago, it was a shed delivery truck in it's past life.

If you stick with Ram 3500 6.7 trucks, they could come equipped with the Aisin automatic transmission rather than the 68rfe. Mine has the Aisin since it was originally a cab & chassis. I would definitely recommend searching for an Aisin equipped truck.

Curtis73 (Forum Supporter) said:

I'm going to go a different way.  If we were comparing the 5.9 Cummins, yes.  The 6.7L is great, but still has all the extra external failure points, which is what will fail on either one.  A properly bulletproofed 6.4L with half the mileage for the same price range?  Further evidence of the Cummins fanboi tax.  Lots of people LOVE their Cummins, and there is a ton of great stuff about them.

Either one will have three times the torque you need to tow
Either one will be better than gas MPG
IMO, the dodge truck that was built around the Cummins is a nightmare.  Terrible materials and build quality, quicker to rust, and don't even get me started on the 68RFE transmission.  When it goes, it won't need a rebuild because the clutches wore out, it will need sprags, a new valve body, and you'll be very lucky if the valve body hasn't caused a crack in the case.  $4000 MINIMUM for a build on someone's bench.  The fact that this one hasn't needed to be remaned twice is a miracle, or maybe it has and the seller isn't disclosing it.  Dodge took a rattly inline 6 diesel and put a transmission behind it that is basically a 727/A518 that has been continually band-aided since 1985.  The 5R110 in the Ford, however, has line pressures that tend to be lower than some tow-folk like, which is easily fixed with a $60 kit and an hour.  My years running transmission repair shops has me a little on a soapbox about transmissions... things that many people overlook.

Familiarize yourself with B10 and B50 life expectancy.  They are mileage numbers that correspond to relative lifespan at which 10% and 50% of diesel engines require a major overhaul.  These are not subjective, they are reported data from millions of engines.  The B50 lifespan (that is to say that 50% of a certain engine in a production has needed a major overhaul) for the 6.4L Stroke is 375,000.  The B50 life of a 6.7L Cummins is 250,000.   That Cummins is fast approaching almost double of its life expectancy based on the average.  Buying that Cummins is like adopting a 17-year-old dog with cancer and one leg.

The 6.4L however is tucked inside one of the best-built, better quality, better assembly vehicles I have ever owned.  When I would go from my F250 to a 6.7L Ram at work, it was like going from an Escalade to a 1975 IH Scout.  Buzzes, rattles, squeaks, vibrations, punishing ride, torn seats at 80k, and good lord you practically had to take off your seatbelt to reach the radio or the cup holders.  They have become much better in the later years, but still they're a big plastic rattlebox.

I realize that truck and diesel opinions are like buttholes.  Every one has one and they all stink.  I'm not brand loyal by any means.  I've owned them all, and worked for a utility company in maintenance where we had four brands of truck, gas, and diesel.  The only ones I've consistently regretted were the Rams.

If you find a good Cummins and you like it, go for it.  In all honesty, maybe you're the type of person who prefers max towing capacity and you'll sacrifice some other amenities.  No judgement.  I'm speaking for myself here.  Just please don't drink the Cummins Kool Aid.  You'll overpay and get a great engine with a glass transmission and less "truck" for your money.  Even the venerable 5.9L was wonderful, but the fanbois made them so expensive that it wasn't worth the buy-in back in the 90s and 2000s

Any chance the IH MaxxForce could be affecting those B50 numbers?  If it's 375000 for the 6.4 in Super Duty Ford trucks, I'm finding that hard to believe.  That engine tended to do quite a bit better in school busses and medium duty Navistar trucks though - and I can see those with serious miles.

So I have had good luck with a 6.4 but I just used it as a truck to tow cars with and didn't pretend it was a race car as diesel idiots tend to do.  If given the choice I would probably go Cummins tho.  My thought process is diesel engines are supposed to be a straight 6, if they were supposed to be any other configuration tractor trailers and industrial applications would use them but they stick with the straight 6....gotta be a reason for that.

In reply to RonnieFnD :

More main bearings and excellent inherent balance. It's no coincidence that a lot of the legendary long-lived engines are straight sixes.

A 401 CJ said:

It's common knowledge that the 6.4 (MaxxForce in IH parlance) is a turd.  But if you can make it stay together, and a few have, that engine will best all challengers in the power wars.  All of them.  It can make  REDONKULOUS power.  Look at the rods it uses.  It makes even the 6.7 PS rods look puny by comparison.

But I'd avoid it unless I was a sled puller or drag racer.

All the power in the world doesn't matter if you have a crappy transmission.

I'd rather have a 4.6 with the accelerator permanently bolted to the firewall if it meant the transmission wasn't a ticking time bomb.

Such a tough call.  I just don't want to deal with the 6.7 Powerstroke, but hear the concerns about the 6.0 and 6.4.  Most of the Cummins or Duramax under $20k are old and/or high miles.