Duramax vs. Cummins- Need some feedback

[Shawn Blair]

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

[james schaechter]

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.

[Ed Wright]

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.

[Rob Petrie E395]

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

[Run to Rund]

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.

[Troy Henderson]

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

[Chris1529]

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.

[Jim Wahl]

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

[Chris1529]

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.

[CrateCamaro]

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.