Cummins vs Powerstroke vs Duramax

doc_speeder wrote: The 2006-2007 LBZ IMO is the truck you want. 6 speed Allison, virtually bulletproof LBZ Duramax (in stock or close to stock tune)

Agreed as far as GMs are concerned. Best of the Dmax without the DPF.

I have owned a couple 7.3L strokes. Amazing engines that need ridiculously little maintenance. They will need a GPR every 60-100k, and they'll need a CPS at 200k. Otherwise, they are remarkably simple and bulletproof. Problem is, finding one that isn't completely clapped out is tough since they haven't been made for years.

The 6.0L is actually a fine longblock, but like you mentioned, head bolts, EGR, and a few other things are hurdles that need to be addressed, and they can be massively expensive fixes especially considering that many of those fixes require lifting the cab off the frame. However, if they are fixed by the previous owner, I wouldn't worry too much about it. The 6.0L reputation does tend to keep its resale value down, which helps you on the purchasing end, but hurts you on the resale side.

I would say the same about the LB7 Duramax. They had issues with injectors which can be overcome, but unless you want a big cost in your own wallet, make sure they've been done. I have an LB7 and an LMM. I much prefer the LB7 for the 930 lb-ft of (easy to modify) RWTq, but the 6 speed allison behind the LMM is a much nicer box. If I had my way (and Dad didn't own half of each truck) I would trade them both on an LLY/LBZ truck to get the best of both. Biggest complaint about the LMM is the DPF which really hurts fuel economy. I can get 21 empty in the LB7 (SRW with 3.73s), but can hardly muster 16 empty in the LMM (DRW with 4.10s)

Cummins is a genuine workhorse. The 5.9L 12v mechanical is one of the finest things put in a truck. The 24v is also a wonderful engine, but the very first thing I would do is make sure it has an adequate lift pump. If the lift pump goes kaput, it will fry the injector pump pretty quickly and expensively. I have no personal experience with the bigger Cummins other than driving a couple briefly.

As far as the truck is concerned, that is more controversial than asking which diesel is best, so I'll offer my opinion and it should be taken as such. Having owned several GM diesels, several Ford diesels, and driven a couple Dodge diesels, I would go in this order (speaking of the truck itself, not the driveline): Ford, followed very closely by GM, and an extremely distant third Dodge. I mean extremely distant. As in; I love the Cummins, but if I were given a Dodge diesel, I would park it in my driveway and put it on Craigslist immediately, then take that money and go out and buy a Ford or GM. Either that, or I would yank the Cummins out of the Dodge and drop it in an F250. I really really detest Dodge trucks. Can you tell?

In my opinion (again opinion), Ford uses the highest quality materials and assembly of the three. The cheap, base model fabric seats in both of my Fords looks darn near brand new with a 150k miles, while the leather in the LB7 had to be replaced at 70k because it completely fell apart. The high-end cloth in the LMM is showing wear with a scant 23k on the odometer.

My suggestion; test drive all of them at a dealer. While you're in them, push on the dashboard and trim pieces. The Dodge is full-on plastic that squeaks and rattles. The GM is not far behind. The Ford is quiet and beefy stuff.

So if I had the dream combo, it would be an F250 with either a 12v Cummins or LLY/LBZ Dmax, and a 6 speed allison. (or an NV5600).

Fueled by Caffeine wrote: I keep hearing about the great allison tranmssion in the Bowties. Spill it folks?

Having worked several years as a transmission repair shop manager, I saw one Allison come in for a rebuild. Dodge transmissions (46, 47, 48RE) paid a very large proportion of my salary. Ford's 4R100 offered a pretty fair share to my paycheck as well. The problem is, the Dodge and Ford boxes are (in distant relation) basically beefed up A518s and C6s. The overall clutch diameter and basic design is a beefed up version of a small-diameter box from the 70s. Same was true of GMs 4L80E. GM did a wise thing going Allison.

The Allison is a true, medium-duty truck transmission. It is used in NQ/NPR trucks up to 23k GVWR (I think... maybe 20k). There are some weaknesses; mostly due to GM softening up the shifts for use in a passenger truck, but they are quite wonderful boxes. The one we tore apart at the shop had simply worn the clutches after 450k in an Isuzu box truck, but the hard parts were fine.

Our 2006 F250 6.0L with an EGR delete. It dropped 1 MPG with the EGR delete installed. That's loaded and unloaded.

Tows like a dream. Been thru 23 states with 20 foot enclosed. 128K to date.

I just had the 4R100 in the wife's 2000 PSD rebuilt at 275,000 miles and a lot of those miles are with a horse trailer in tow.

I had the rebuild done because the trans puked the front pump seal and I figured if that trans had to come out with that kind of mileage on it, it was going back in with new guts.

My transmission guy rebuilt it and installed a trans-go tugger shift kit and a torque converter from the 6.0 trucks.

I swapped in a new, larger cooler and moved it from behind the bumper where it got no airflow to behind the grille.

Huge improvement, it shifts faster without being harsh and the truck runs a bit cooler.

Zombie thread, canoe removed 

I thought this thread was going to be about male enhancement treatment options and was solely disappointed. 

Good thread.  I read it all.  

A wise old farmer once told me “a Powerstroke is a decent engine in a decent truck.  A Cummins is a phenomenal engine in a sh_tcan truck.”

A 401 CJ said:

Good thread.  I read it all.  

 

A wise old farmer once told me “a Powerstroke is a decent engine in a decent truck.  A Cummins is a phenomenal engine in a sh_tcan truck.”

My tenant owns a 12V cummins.

I didn't think anything rattled more than a 7.3 Powerstroke but here we are.

In reply to ShawnG :

No kidding. I'm sure my neighbors almost threw a party when I sold mine.  It seemed like that SOB was waking the dead when I started it up on a cold morning at 5AM to go to work. I plugging it in didn't do squat for making less noise. 

Although I did make a point of giving the pedal a good whack when I drove past the home of the guy who likes to start up his chopper at 7AM on a Sunday morning...  

I'm sure my 7.3 IDI E350 will have few fans when it finally makes it home, although it at least has the stock exhaust vs. the 4" turbo-back system the 12V had.

I did 4” turbo back on my 7.3.  With muffler —not straight because I refuse to join that moronic club.  It’s quieter than stock I think.  At least from the cab.  It’s a Diamond Eye I got from Summit.  Not a bad kit.

LMM Duramax here. No major work. Current mileage: 

And yes I’m aware the the check engine light is on. Two bad glow plugs and a deleted DPF without a tune will do that. Oh and my truck is telling me it’s time for a bowl of soup. 

In reply to A 401 CJ :

Mine came with the truck. No cat. No muffler. Just pipe from the turbo to behind the rear wheel.  My mechanic said I had to put something that resembled a muffler on it to pass inspection, so I bought a $100 muffler than was essentially a resonator since you could look straight through it. It made reduced the dB by roughly zero.  A coworker said he could still hear the truck accelerating a half a mile away when he was sitting outside the office eating lunch.  Otherwise, the truck was stock. I replaced the mudder tires and aftermarket rims with take-off OE 17" steel rims and 265/70-17 street tires. I pulled off the brush guard as well since the last thing that truck needed was to be any longer.

The truck is still in my profile "garage".  This picture was taken the day after I bought it in 2007:

The muffler in the Diamond Eye kit was just a straight through resonator too.  This truck did not ever have a cat as near as I can tell.  Late year ‘99.  It’s not “quiet” by any means.  I mean it is a 7.3.  But if it’s any louder than stock it isn’t noticeable.  I ran it with just the downpipe to see how it would sound.  It still wasn’t that loud.  The turbo was a lot more pronounced though.

Good this thread was revived, as it's relevant to my interests.

I'd like to upgrade from 5.4L 3V F-350 regular cab to a 6.4L or 6.7L F-350 crew cab dually.  I'll be towing a 26' enclosed with a 3,300# race car (plus tools, spares, etc) and while my 5.4L will do it on paper, throw some significant hills in there and it will be painful for all involved.  I also use this truck as a daily driver for my business - the hauling/towing capacity isn't as big of a deal as the 8' bed is.  The 5.4L Triton will probably stick around either way as a plow beast....rather use that one during the winter than beat the hell out of a newer truck.

I've found a 2010 F-350 I like with the 6.4L, low miles, and a fair price.  Last year before DEF, does have a DPF that apparently causes a fair bit of regen (and corresponding MPG drop).  My understanding is that the 6.4L is better than the 6.0L (before bulletproofing), but isn't exactly stingy with fuel, and the cab needs to be pulled for any major service (HPFP replacement).

I've also found a 2015 F-350 and 2016 F-450 (yowza!) that fit the criteria, but they are $10K and $18K more respectively.  The 2015+ 6.7L gets improved turbos, ALL of the torque, and is generally regarded as a homerun for Ford.

I would most likely do a DPF and EGR delete and retune either, so consider that a wash.  This is a 10-11 year truck that needs to carry people, work gear, and haul race cars well 6-10 times a year.  The 6.7L trucks are towards the top of my budget, while the price for the 6.4L is actually better than planned.

Any thoughts from those that have owned one or both?

In reply to Rotaryracer :

I have a 6.4 in my RV.

My thoughts are, get it deleted and tuned, drive it nicely and change the filters often. It will fire hose in fuel to keep up with the boost, which corresponds directly to MPG's.....

Deleted and tuned are big on this, the regen uses the back two cylinder injectors firing on the exhaust stroke the pump raw fuel into the DPF filter. This fuel washes the oil off those two cylinders.

Cab off repair bills suck. Check the flex pipes for cracks before you buy. Firewall will be a little sooty, and you can kinda hear them hissing. Common issue and a PITA to do.

Related questions:

Is it possible find a crew-cab short bed Ford 7.3L, either prior to 99, or up until 03? 

Has Ram quality improved enough that more recent iterations might combine the best attributes of Cummins diesels with a more decent truck? It seems like the "AEV Era" of Ram 2015+ has drastically improved the truck.

It'll be interesting to see how the "Scorpion" 6.3L V8 PowerStroke is in 10 years, as the new Ford's are pretty nice. 

We had a 2000 shortbox crewcab 7.3 Superduty.

It got stolen and I had a huge fight with the insurance company. They claimed it wasn't worth anything because they couldn't find any equivalent trucks for sale so it must not be worth anything.

I argued that it was a bit of a unicorn and the only one I could find was in Florida and asking $13k.

We settled on $8k and I still think I got the shaft.

Current rams are way better than ones I’ve previously been in.  I like my ‘16.  Base work truck interior so yards of textured plastic, but way easier to clean than leather.  Ergonomics worked for me better than GM, and I couldn’t live with the grille of the super duty.  At 5/100, i’m going to do whichever deletes/tune are for longevity and mileage but until then it’s FCA’s truck to deal with.  It’s been in for one real problem, shift solenoid pack went bad, but it was under warranty and they later issued a recall for it.  

Book value is currently a couple thousand under what i paid because i got a very good deal, very few things hold their value like a cummins ram

ShawnG said:

We had a 2000 shortbox crewcab 7.3 Superduty.

It got stolen and I had a huge fight with the insurance company. They claimed it wasn't worth anything because they couldn't find any equivalent trucks for sale so it must not be worth anything.

I argued that it was a bit of a unicorn and the only one I could find was in Florida and asking $13k.

We settled on $8k and I still think I got the shaft.

Huh, weird.  With the Chevys, the crewcab shortbed is the most common configuration, CC long beds are the unicorns.

I’d be loath to delete one beyond software.  Too easy for laws to be changed and next thing you know your truck isn’t street legal.

A 401 CJ said:

I’d be loath to delete one beyond software.  Too easy for laws to be changed and next thing you know your truck isn’t street legal.

If you're going to do it, keep the parts.  Lots of folks in CA deleted emissions equipment on their diesel trucks back when there were no smog tests for them and threw the parts away, then when they were added they had to go buy new ones.

In reply to Rotaryracer :

In my opinion the 6.4 is the worst of the 7.3, 6.0, 6.4, 6.7. You must delete it and pray for 12mpg lol.

I currently have a 7.3 but had a 2006 f250 6.0 with egr and oil cooler mods but stock tune. The 7.3 has only needed external things like alternator, batteries, etc. The 6.0 needed nothing in my ownership. I've never tuned either and the 7.3 has a straight pipe exhaust (really loud lol).

I miss the speed and extra horsepower of my 6.0 and I would get one again as long as it was never tuned. If I had the choice between a 6.4 and 6.7 I'd get the 6.7. Especially if I was using it to work daily.