Anyone ever "de-tuned" a Cummins 5.9 for mileage?

[buickanddeere]

Any diesel or gas turbine has lousy part load fuel efficiency. Take a look at any diesel tractor on the Nebraska tractor test site for the HP per lb fuel per hour. At rated load, 50% and 25% load.
Light duty diesels just don't have the advantage over today's light duty gassers . Fuel injection and lockup torque OD transmissions narrowed the gap up to 2007. After 2007 it's difficult to make a cost per mile case to justify a diesel. In particular now with the direct injection gas engines.

 

[sd455dan]

Any diesel or gas turbine has lousy part load fuel efficiency. Take a look at any diesel tractor on the Nebraska tractor test site for the HP per lb fuel per hour. At rated load, 50% and 25% load.
Light duty diesels just don't have the advantage over today's light duty gassers . Fuel injection and lockup torque OD transmissions narrowed the gap up to 2007. After 2007 it's difficult to make a cost per mile case to justify a diesel. In particular now with the direct injection gas engines.

How many of those tractors don't employ turbo charging(lower efficiency),, and if they hadn't saddled the newer diesels with tier 4 , and the diesel cost due to removing the sulfur, it would be diesels sounds like the newest vehicle he was considering was 4-6 years old so it sounds like he would not get anything that the new regs have hurt the mileage on...

 

[Peacock]

Tractor engines are designed to work under heavy load. A truck engine needs to be able to operate well under a much broader set of conditions.

The injection pump is calibrated differently for the different operating parameters.

 

[Peacock]

Had to edit my post as it made no sense at all. Not sure how that happened...gonna blame it on the smart phone...

 

[Nooodles]

I kind of wonder about Detroit and the gas mileage thing. My first new Chevy pickup was a 1/2 ton 4x4 5.7 liter. It had 195 HP and did what I needed a truck to do and got about 15 MPG on the highway. My present 2007 4x4 Chevy is a 5.3 liter with over 300 HP and still gets about 15 MPG highway. I really don't need 300 HP. I wonder what kind of mileage my 2007 5.3 would get if it was only 195 HP.

Seriously?? Why the heck did you buy it then. My old dodge Dakota with 6 banger in It with under 200 hp. It couldn't get out of its own way going up a hill with 190 hp.

 

[Rustyiron]

Seriously?? Why the heck did you buy it then. My old dodge Dakota with 6 banger in It with under 200 hp. It couldn't get out of its own way going up a hill with 190 hp.

A hill..... in Delaware?:laughing:

 

[buickanddeere]

Seriously?? Why the heck did you buy it then. My old dodge Dakota with 6 banger in It with under 200 hp. It couldn't get out of its own way going up a hill with 190 hp.

Purchase the 195HP 4.3L six and find out.
The 4.3L walks all over the old 350 four barrel in power, economy and reliability.

 

[sd455dan]

Purchase the 195HP 4.3L six and find out.
The 4.3L walks all over the old 350 four barrel in power, economy and reliability.

Given a choice I'll take ANY 225 or 3.8 Buick V6 over the 4.3 and a warmed over gnX engine is in a class of 1 But gm let Chevy lop the front off the small block instead, at least they incorporated the vortec chamber design...And now we have the Ls series, really quite an impressive transformation. but when it comes to V6 engines Buicks will always be my favorites, that includes working on or repairing them...

 

[buickanddeere]

Buick 3.8/231 is a V8 missing two cylinders. Had to offset the rod journals to make it an even fire. Have a a TI SFI with 296,000 miles on the original bottom

 

[Peacock]

Buick 3.8/231 is a V8 missing two cylinders. Had to offset the rod journals to make it an even fire. Have a a TI SFI with 296,000 miles on the original bottom

They are a pretty bullet proof engine. I can only imagine how well the turbo engines would have done in a truck. Huge torque at very low rpms.