Duramax vs. Cummins- Need some feedback
 

My uncle is contemplating on buying a new dually. Are there comparison tests out there? How about durability, and mileage? The Dodge and Chevy are the trucks of interest. Any owners out there that could share experiences would be greatly appreciated.

Re: Duramax vs. Cummins- Need some feedback
 

We've had great luck with the Duramax powered trucks. Excellent mileage and power, and good reliability. So far, in our group, that's about a dozen of them, and only one gave any real trouble. It was not all the fault of the truck. It was already long out of warranty, the aftermarket shop screwed it up badly, and it took the dealer 3 tries to fix it. From my experience with the Dodge and the Cummins, you get either mileage or power, but not both. If you get one with a 3.55 or 3.73 gear, they get decent mileage, but don't run that well. If you get one with a 4.11, it runs good, but the mileage is nothing to brag about. And the BullyDog stuff makes the Duramax get better mileage and more power.

Re: Duramax vs. Cummins- Need some feedback
 

My father has a cummins in his it now has over 300K on it and other than adjusting valves as recomended and other regular maint it has given us very few problems, the worst being getting Ball Joints to last. This a farm truck that spends alot of its time loaded with a large cattle trailer behind it and it still went 250K before it got its first clutch. It has started leaking oil from the front cover area which is no big deal considering the milage and would be no problem to fix if I could just get him to let me have it for a day or 2. I am not a Dodge fan and cringed when he said that is what he wanted, but this has been one tuff truck. We also have a gas powered GM that I pull my car with and another with a Duramax. I am a die hard GM fan and I can say I HATE this Duramax truck. It spends more time at the dealer getting more BS problems fixed under warranty than it does here. It was originally bought to pull my GN car trailer and for pulling the cattle trailer when he goes to shows and sales but with all that has gone on with it we dont use it for that very much. When we first got it we had nothing but problems with fuel filters and check engine lights seems to be better now that I switched it over from a GM filter to a Napa 3910 but still needs replacement faster than any diesel I see and we see a ton of them in my shop since this is farm country and everybody seems to own at least one truck. The blower motor burns up a resistor pack and the connector going into it about every 6 months no big deal to fix but GM needs to get off thier buts and find a real fix and not just keep on replacing it with the same parts. The cabin air filter has to be changed real often or smells like a garbage dump inside in the summer. There is more but I think you get the idea. Has it had any major problems no, does it pull like a freight train yes, does it drive like a car yes. With the exception of the filters and the blower I am starting to believe I just had bad luck with this truck as like I wrote earlier I see a ton of them and nobody else seems to have as many problems with thiers. Now if you want to hear about some real problems as me about a Ford some of those owners have a real problem on their hands.
Hope this helps
Rob

Re: Duramax vs. Cummins- Need some feedback
 

I see quite a few Duramuts in our shop (chevy dealer) mostly small issues very few major problems. The most problems we see are usually caused by "power up" software or controllers. Please be aware that if you add one of these to your Chevy diesel and you have a failure GM is aware of what is causing them and will deny any Warranty repairs. Even if you have a programmable that you can switch back and forth to stock setting it leaves a trace in the software that can be detected by GM. Just want to give you guys a HEADS UP so you don't get denied. Personally I pull with a 7.3 Power stroke never had a moments trouble with it, it will pull anything you hook to it and delivers good mileage, obviously the 6.0 and 6.4 has had issues.The Cummins I have no personal experience with however the guys I know that have them LOVE the Engines don't have alot to say about the trucks themselves though. You have to remember Cummins was building diesels before GM or Ford and have much more experience doing so. Joe

Re: Duramax vs. Cummins- Need some feedback
 

I have a '96 Dodge Cummins with 250K on it. Most of it pulling a 50' trailer w/2 cars. It gets 11-13 pulling and over 20 empty. The clutch went @ 200K. It's by far the best vehicle I've ever owned. It doesn't have the EFI so I had the pump worked on and the turbo turned up right after I got it. It wouldn't pull before that. It has all the power I need. I run 70-75 pulling the trailer. That said, I've heard good things about the Duramax. I don't know anybody that has put my kind of miles on one. I do know what my Dodge has done though. I plan to keep right on going with it.

Re: Duramax vs. Cummins- Need some feedback
 

I have a 2002 Dodge Dually with the manual 6spd. I added the Edge with Attitude to add display of boost,EGT, and lift pump. I already had 18MPG unloaded, now with Edge on milage mode it is a different truck and has increased to 19MPG. I have had no problems and am the second owner. Truck has 71,000 miles and all that has been done is replacing all brake rotors and pads. Only issue is it is noisy.

Sean

Re: Duramax vs. Cummins- Need some feedback
 

I would think the duramax with the Alison transmission would be a consideration.

Re: Duramax vs. Cummins- Need some feedback
 

I have not owned a Duramax but I do have a motorhome with a Cummins.
I can tell you from experience that my Cummins has had no major issues but the small things have been a problem.
Another major issue is that Cummins has NO Procedure For Recall problems.
I had a controls issue and after I was towed to the Cummins shop I was told there was a recall on the parts which were bad. I said I did not receive the recall. I was then told Cummins does not send out recalls they just wait for a failure. Cummins does not have a recall system for owners notifying them of a recall.
So if you have a Cummins engine and it has a recall issue the only way you will know is if you research recalls on a regular basis or have a failure you will never know of it.
I have an issue with that after purchase of their product.
That is really an issue when a formerly recalled part fails after the warranty expires.
The owner then pays for the recalled part and may never know about it.
Been There Done That!!!!!!!!!!!
My 2 Cents

Re: Duramax vs. Cummins- Need some feedback
 

I have a 2001 Dodge with a Cummins 6 speed, only 50,000 miles and I get over 13 miles to the gallon pulling a 38' gooseneck ... it's not even broke in yet ... excellent truck, great thru the mountains. I get about 20 mpg empty ...

Re: Duramax vs. Cummins- Need some feedback
 

I would highly recommend the Duramax. I have a 2005 Chevrolet dually with the Duramax/Allison combination. I have 125,000 miles on it. This truck has not had any mechanical problems at all. The only repair I have had to do was a wheel bearing on the front passenger side. I tow a 40 ft gooseneck trailer, loaded. About 16,000 lbs. The truck pulls very good, lots of power, great breaks, excellent ride. The overall quality of the truck is excellent. The duramax engine is also very quiet. I get about 11 mpg towing the trailer if I keep the speed around 70 mph. The truck will run much faster but the fuel mileage will drop to about 9.5 mpg. I get 17 - 18 mpg as just a pick up truck depending on my driving habits. I have a friend with a Dodge with a Cummins. He has had some problems with the trans and the electrical. The two trucks dont compare in quality.
I have not added any power adders with the exception of a KN filter. The truck really does not need anything added.
The allison trans is far superior to anything else on the market in this size truck. It shifts perfectly and in the tow haul mode it gives you an engine braking feature that works real good when towing a heavy trailer.My truck has the 5 speed version. The new trucks have a 6 speed auto trans in them. Should be even better.

Re: Duramax vs. Cummins- Need some feedback
 

I have a '06 Chevy 3500 dually with the Duramax/Allison combination. I have used it for the last year and a half delivering RV's from the factory to dealers throughout the USA and Canada. I have put on 230,000+ miles and have had no problems at all. I bought an Edge controller and use the towing mode when I'm towing and the economy mode when not towing. Watching my driving habits has let me get this thing to get 14+ mpg towing a large fifth wheel camper and to get 22+ mpg running down the highway at 70 mph with no trailer. I switched the trans and differential to synthetic oil and with the braking feature of the Allison, the truck still has the original brakes on it. I looked at them when I changed from the aluminum wheels to the steel ones for the winter and the pads all look like new. The engine is quiet and starts in the cold very well.Last winter I ran to Grand Prairie, Alberta (about 250 miles northwest of Edmonton) and back on a pretty regular basis. The fuel mileage dropped off a lot but the truck never gave me a minutes trouble even at -50 degrees. A lot of the other guys I worked with had Dodges and they do a good job, the Cummins is a heck of a motor and the trucks are a lot better than they were a few years ago. I could outrun most of them and got better mileage than they did. My truck has the factory air cleaner and exhaust and all I do is boost it a little bit when I'm towing. The Duramax/Allison Chevy is my truck of choice, hands down.

Re: Duramax vs. Cummins- Need some feedback
 

what's a duramax or maxi or whatever

Re: Duramax vs. Cummins- Need some feedback
 

I have an '03 Duramax Dually w/ 73K, and it runs and pulls hard w/ the best of 'em, and gets about 12.8 mpg towing, and 20 non-tow. However, it has a feature that switches the charge from the alternator between the two batteries, that causes one battery to overcharge and "puke' acid. I have had the batteries replaced three times under the NAPA battery warranty. I have had the system checked and can find no malfunction in the switching program. Anyone out there ever had a similar problem?

Re: Duramax vs. Cummins- Need some feedback
 

I have an 03 Dodge with a Cummins & a 6-speed I drove it to work all week last week it took 19.4 gals to fill & had 399.7 miles on the odometer...The thing will/can pull my 24' box with a 3500# Cutlass in it 85Mph! The only thing I've had to fix was a U-joint...but I guess 600 foot Lbs of torque will do that! ;)

Re: Duramax vs. Cummins- Need some feedback
 

There seems to be alot of guys on here with dodges. Have any of you guys had high gear go out of your truck (manual trans here) We saw several including one we had that would be towing down the interstate and all the sudden it was like it jumped out of gear and goto the rev limiter. When you tried to put it back in gear it was gone although if you jumped down a gear you could still get home or to shop to get fixed. Most were covered under warranty still so we never fixed one at my place but I am wondering if the later models are fixed with a update from the factory or is this still happening? Sorry to sidetrack but I thought it might be seen by more guys here rather than start a new thread. We were seeing this regularlly in the 98,99 model years maybe others cant remember back that far.
Rob

Re: Duramax vs. Cummins- Need some feedback
 

I had a 2006 Duramax Dually and it did great, no problems. I would say that you might avoid the new body style GMs because of some of the changes made in those two years have seen alot of issues. If you go GM i would say 2006 or older. However alot of Dodges seem to have manual trans. in them. The allison trans is a awsome trans and I would suggest you go with that trans no matter what you buy.

Re: Duramax vs. Cummins- Need some feedback
 

I have a 2006 Duramax duallie with allision trans. I've had it since new and is a great truck. I tow a 43 ft gooseneck and it gets around 11mpg. Has great power towing hills.I went to indy in '08 with an open tralier and it got about 14 mpg, from seattle to indy. We added a 100 fuel tank, and we can make it from seattle to pomona on 1 tank. I would recomend a auxiliary fuel tank, especially if your are towing a bigger tralier. Its nice to be able to go a long ways and not stop.

Re: Duramax vs. Cummins- Need some feedback
 

Rob Petrie, I Have a 96 Dodge Cummins Duallie with a 5 speed, and 312,000 mi and in the first 100K I lost 5th gear just the way you did! What happens is there is a waverly?, washer held with a locking nut! when that washer destroys its self, the gear will ride fore and aft and bang on the lock nut, and then there will be times when the gear will only be engaged with half it's gear depth and fail! I had this happen 5 times, and the fifth time they (Chrysler) replaced the entire trans, drive shaft, flywheel, clutch, pressure plate, throw out bearing, and all labor under warrenty at 98.000 mi. They Bitched, but my dealer got it taken care of! Its still in there and working great! The pump has been screwed with, on there nickel, and empty it gets 24 MPG w/3.55 Gear. Pulling a 28 Pace Big Foot loaded at 65MPH 13-14MPG. Cant get rid of it yet ,the rings are just seating. ........... Later, Merry Christmas To all, John & Ginny Lang

Re: Duramax vs. Cummins- Need some feedback
 

John
Thanks for the reply. Have you heard how long this went on before they fixed the problem. I know the 99 and I think some into 00 did it but not sure if it went on after that but curious to know. The newer trucks have 6 speeds not sure how many model years had that 5 speed.

Re: Duramax vs. Cummins- Need some feedback
 

I've towed a bunch of miles with both and would take the Cummins over the Duramax everytime especially for durability..As far as automatics go the allison is as good as it gets(though not indestructable),Dodge's automatic is definately better than it used to be with the exhaust brake etc..and the 6-spd manuals are both comparable. The other differences between the two would be a toss up IMO.

Re: Duramax vs. Cummins- Need some feedback
 

Dodge,Cummins,6-speed,Mileage,it's really an easy choice. Besides do you really want to buy an Izusu engine?

Re: Duramax vs. Cummins- Need some feedback
 

I have a 2002 GMC Duramax 6 speed manual 4 x4 crew cab 2500hd. I have 192k on it. The injectors were all replaced under warranty and the dual mass flywheel was replaced a couple of times under warranty. I love the truck. In the summer, I get up to 24 hwy empty with 3.73 gears and always over 20. In the winter about 2 less mpg avg. Towing I can count on 15 with a 24 ft tag going 75. No mods or programmers.

The only complaint is with the flywheel. GM screwed that deal up and added a healthy dose of CYA when I found out the new improved flywheel was the same junk and would not hold up. There is a fix and it works great. A single mass flywheel. I did that at 110k and have had no issues with that. If you look for a GM stick Duramax, if it still has a dual mass flywheel. Figure in 1200. for the southbend kit if youinstall it yourself and you will be good to go.

Other than that, I plan on going to 300k before I think of getting a newer one. By the way, I would stay away from any of the diesels with the DPF. I think that is 2008 and newer. MPG suffers and I just don't think that is the best way to control the emmissions.

Re: Duramax vs. Cummins- Need some feedback
 

James is correct about the DPF, except that started in mid 2007 for the Duramax. That thing and it's calibration, is a mileage killer. The '06 is the last year to for sure avoid that thing. You can buy an "off-road" exhaust system to get rid of it, but it is illegal as hell. If, however, somebody installs the off-road exhaust system, I (and others) have a nice running calibration for them. Off-road use only, you understand. If you plan to buy a programmer for one, be advised the '07 & later Duramax computers store the checksums and CVN numbers (Just another, redudent checksum) for the last ten calibrations that have been loaded. I have heard guys say "I'll just program it back to stock ten times with my hand-held before I go in for warantee Work". That won't get it, as it only stores one copy of a given set of checksums and CVNs. Only way around it would be to buy a spare computer, and lay the original aside to be installed before taking it back to the dealership. Of course, if you have changed to the off-road exhaust your warantee is gone anyway. Some of these "tuners" and popular hand-helds get carried away with power increases. You can make crazy power increases with a diesel, but it tears stuff up. No reason to expect GM to cover that, but some try to slide that by anyway. All I'll do to them is 60 to 75 hp at the tires and 1 to 1.5 mpg. I'll let the other guys make 200+ more hp and tear things up.

Re: Duramax vs. Cummins- Need some feedback
 

On the warranty deal and using a programmer. Buy a clutch from Napa, Carquest, Federated, ect and you will find the first thing you see when you open the box is a paper stating that if the engine tuning has been modifed there is no warranty on their product. I agree with Ed alot of these trucks are tuned up way too far I have seen some that sound like a Peterbuilt with with 6" stacks and smoke like a freight train

Re: Duramax vs. Cummins- Need some feedback
 

5th gear goes out on the New Venture 4500 5-speeds. the fix is at www.standardtransmission.com

For lots on the Cummins/Dodge, see www.turbodieselregister.com

For clutches, www.southbendclutch.com and talk to Peter.

Re: Duramax vs. Cummins- Need some feedback
 

2002 3/4 ton Duramax. Bought it in the spring with 76,xxx miles on it. Had the injectors replaced at 65,xxx. Its got 94,xxx on it now. Most of them were from towing a 28' tag at 10,000 lbs. I put a Banks programmer on it with exhaust and K & N filter I bought off ebay used. I also run some Bio Diesel in it. Its impressive. It pulls the hills here in the midwest w/o clicking out of overdrive. Low teens towing 70mph.

I took it to the track here on t&t night and let the fiance drive it. Was running low 14's with a 2.5 sec short time :eek:

Re: Duramax vs. Cummins- Need some feedback
 

2009 F-350 4x4 w/ 550 Cat.

at least that is what I asked Santa for!

in real life, I have a 2004.5 Dodge 2500 4x4 quad cab. 6 speed
gets about 9 mpg with a 26' tag here in the mountains. On flat, I may get it up to about 11 if I drive it carefully.

Re: Duramax vs. Cummins- Need some feedback
 

I have an '05 Dodge 2500 Quad Cab Heavy Duty with the 11" rear and a 3.73 gear. I get 15+ mpg towing a 24' Featherlite enclosed trailer. The same towing my 30' 5th wheel RV trailer. I get 17-20 mpg around town and 22.5 on the road not towing. I have the Edge programmer and a Volant air intake. I only have 26,000 on it now and the milage gets better as it breaks in. I ran 14.98 at the track spinning badly, as it is a 2WD truck. The trick with mileage on the Cummings engines is to keep your RPM's under 2,000. Anything more greatly reduces fuel mileage.Jim

Re: Duramax vs. Cummins- Need some feedback
 

I agree with keeping the rpms down. my 4x4 with 3.73 gears will get 18-19 not towing, but here in the mid atlantic towing where I go, you can't keep it that low rpm (or at least I don't). There are alot of hills I pull at 2900+ rpm in 5th gear. That equates to about 8.5 mpg. 9 if you average a whole trip.

Re: Duramax vs. Cummins- Need some feedback
 

05 3500 DMAX Dually gets it done for me! Awesome power and I get 13.5mpg and im a meat head with the throttle. I was towing with a 07 Avalanche with the 5.3/325hp and it was getting 14mpg but thats taking my time. I tried towing in OD/towhaul keeping the rpm down and got 14mpg on a 4hr tow to the races. The next time I reset it again and pulled it into 3rd and buzzed the 5.3 a little and it got the same MPG and I got there 20 minutes faster. Sometimes I wonder if the MPG is even close on those trucks. Duramax all the way for sure. Obvously people are going to stick with there brand but actually look at the trucks side by side and try not to be bias of your favorite brand. The GM trucks are built to last, have awesome power and you can take them out to dinner if u wanted too. Obviously if your a crew cab dually owner like myself its hard to park an appartment building size truck like that without running someone or something over. I've drove a cummings 3/4 ton with a Banks 6 Shooter before and it had great power but the trucks feel cheap and really, for a lighter truck it wasn't that much faster/powerfull than my stock Dmax. The interior is real plasticy and they just look cheap and feel cheap IMO. Sierra/Silverado are very comfortable and ride smooth, no road noise, good steering. 45,000 miles and its still driving mint. Just keep up on the fuel filters and you will have no trouble. Dissapointed that the Bullydog voids warrenty. GM needs to wake up.