Why is Dodge/Cummins "easy" on oil?

[Jelly]

I was just thinking about something.

On this site, we routinely see good analysis numbers from Dodge trucks powered by the ISB Cummins engine.

Why is this though?

High Temperatures
Geared Cams
Use of turbo
High loads placed on valvetrain and bearings
Soot load in oil

Are the good analysis numbers simply because of the large oil capacity?

[ October 16, 2003, 04:27 PM: Message edited by: Jelly ]

 

[crashz]

Big oil capacity, efficient cooling system, WAY overbuilt bottom end, efficient fuel management and large oil lines to and from a small turbo.

Basically its like taking a Mack 237, shaving off a couple hundred pounds, and stuffing it into a pick-up. The Dodge trucks will never be able to stress that motor out!

 

[Dr. T]

Aren't all diesel's easier on oil...I mean, they only rev to...like 4k rpms? Are the engine temps cooler too?

 

[Doug Hillary]

Hi,
All diesel engines are certainly not the same as
the main influence on the oil in a diesel is the combustion process. As well as the method of injection, this involves the position of rings, piston design, turbo charger type and combustion chamber profile. Amongst a number of others!

A large sump ( oil pan )capacity also helps a lot and is but one significant thing that seperates Euro, Japanese and American designed diesel engines

An oil that can handle soot well will stand aprt from another with the same API rating

There is no doubt that the move(s) from CG thru CH and to CI have improved the diesel engine's durability all else being equal

Engine revs. is another thing. It is the time spent "under load" ( fuel burnt ) that makes a huge difference in a diesel. Many heavy diesels spend 80%-90% of "engine on time" under load and others - reefer plant engines for one - spend most time at constant revs and load

Even with electronic injection it is idling that is the single most destructive thing to the oil. In normal use idling down is not required ( well longer than 30sec or so ) in most circumstances. A pyrometer is the best indicator of the need to idle down

I hope this helps

 

[MNgopher]

crashz is on to it - a motor that has WAY more potential that can effectively be used in the Dodge pickuptrucks. It really doesn't have to work terribly hard in an application like a light duty pickuptruck. Doesn't mean it never does, just compared to other applications this motor was originally designed for and currently found in this motor is underworked in the dodge trucks.

Part of why they are so popular - an overbuilt engine for the application!

 

[Rebel Rouser]

Does the fact that it's an inline six, compared to a V-8 design, contribute to it's excellant UOA reports?

I've got one, and love it. Cannot say the same for the truck it's mounted in, though.

I will have a second analysis with Amsoil 15-40 soon. The interval will have over 13,000mi on it. Can't wait for the results!

 

[blano]

It shows good #'s because it is a superbly engineered commercial duty engine. Something that can not be said of the duramax or the powerstroke.

 

[Bio-T]

Blano,
If you would remove the arrogant attitude and go to the diesel UOA's, it may shock you to find some good analysis on other brands. You are not in the 2-cycle forum now, so S+it-can your attitude and realize that all big 3 have a fine engine. By the way, let's talk automatic. transmissions sometime on the big 3.

 

[Chris 2421]

Maybe what Blano says is true?? We have several of the 5.9 Cummins in our big semis at the Post Office and they are the best engines we have.They are the same as the Cummins that are in the Dodges.So maybe the fact that the Cummins is a better engine due to it's big truck origins??

And transmissions..what about them??

 

[userfriendly]

Vetteman,
I can't see how your attitude is any different than Blano's.
If I may be so bold in saying so.

 

[Bio-T]

quote:

---

Originally posted by userfriendly:
Vetteman,
I can't see how your attitude is any different than Blano's.
If I may be so bold in saying so.

---

In my response to Blano, you are truly correct.
I was only trying to imply that any of the big 3 have great engines, be it Cummins, Duramax or the Power Stroke. Each owner I guess likes what they own, but I am partial to any of the three.
Sorry that my attitude is showing, maybe a PM to him would have been better.

 

[Shannow]

There's some pictures on the 'net somewhere comparing bearing sizes, rod dimensions, etc of the Cummins versus the powerstroke.

Looks like the Cummins is built big to last a long time, versus a more passenger car type design with the Ford.

Horses for courses, but the Cummins looks like it will outlast many vehicle bodies.

 

[blano]

"and realize that all big 3 have a fine engine"
Vette, Sorry if you think my comments are arrogant. While the duramax and the powerstroke are good motors, they are not as good as a Cummins. Hows that?

 

[Bio-T]

quote:

---

Originally posted by blano:
"and realize that all big 3 have a fine engine"
Vette, Sorry if you think my comments are arrogant. While the duramax and the powerstroke are good motors, they are not as good as a Cummins. Hows that?

---

I respect your opinion on this, but respectfully disagree.

 

[Intelman34]

Here is the rod comparison: http://www.fordcummins.com/images/rodcomparison.jpg

The Cummins B series is offered in vehicles with a 65,000lb GVW (Sterling Acterra Model 8500 for one example). When it is in a Dodge Pickup application, it is not worked very hard at all. If the engine doesn't have to be stressed, then the oil isn't put under extreme conditions.

I like the 7.3L Powerstroke and 6.6L Duramax quite a bit. The new 6.0L PStroke has great potential, it just is having quite a few problems right now. I just happen to like the Cummins best of all and thats why I own one

Heck, even the Dodge wrapped around it has treated me exceptionally well.

 

[csp203]

I know a couple a people that work for ford (I live 10 miles from the world headquarters), I have been told the new powerstokes put up good numbers, (hp/torque) but there have been problems with them. I am sure they will work them out. Then again I would hear the same wispers about the new dodge hemi when it came out.