INteresting discussion on Cummins Power and economy

[amsoilman]

As many of you know, I drive a Cummins (5. 9 L) powered School bus. I was fueling the bus this AM, when a Duramax pulled up and began fueling as well. He asked if my bus was a gas hog. Not really I said, it gets almost 10 MPG. HE says, "My truck would have to be loaded for it to get that kind of mileage! Well, I said, "this bus is not loaded, but it weighs in at 26,000 lbs!" HE says, "What kind of power is in it?" I said, "a Cummins 5. 9 Liter Turbo Diesel, like the ones in the Dodge pickups. " To that he Says, " WOW, is that right?" I said, "Yep! To that he got in his truck and drove away.



I thought it was pretty funny!



BTW, I LOVE that Cummins in my bus! It is the 24V engine, and now has nearly 100,000 on the odometer.



Wayne

amsoilman

 

[Vaughn MacKenzie]

Funny Wayne I wonder if the put DuraMaxes in school buses?



Speaking of Cummins powered School buses, my neighbor tells me most of the Kennewick school district's school buses are 12-valves and the pumps on most of them have been tampered with and tweaked 'cause the drivers want more "git up an' go. " He works at a diesel injector shop and the maintenance foreman sometimes asks for new seals so he can hide the evidence



Vaughn

 

[amsoilman]

No Vaughn,

I've not seen any School buses with a Duramax engine. Infact I haven't seen a Powerstroke in one either. Most all of ours have the Cummins, some are the "C" models, but most are the 5. 9 B's. We have over 200 buses in our fleet, and all but 4 are "Bluebirds".



Wayne

amsoilman

 

[Big_Daddy_T]

Technically the designation for a powerstroke is t444p and is rated light duty. The one is school buses is a t444e which is supposed to be rated medium duty. Ive never been able to see one in action so I cannot tell. They use the t444ps in the f650s and f750s but they are governed much lower than the light duty trucks. I also believe the t444e has a larger oil capacity. Which I would think would allow the heui injectors to work better. More consistent medium.



The school buses around here when I was growing up used a t444e. I could tell by the exhaust note as my dad has owned a few 7. 3s. Another company now has the contract and they run small cats mostly. I have been trying to find out which one. Most drivers are ignorant. Interesting note. They have a couple 7. 3s and they are goverened to run a lot faster down the highway than the cats. So the drivers look forward to running the 7. 3s.

 

[blacksheepdiesel]

You can see the bus I own in my sig...



I ordered it with the Cummins ISB (24 valve) because I already owned my 1989 Dodge Cummins and loved it!



The cool thing when I ordered my bus was that Freightliner had only been in the bus chassis business for one year and they were pushing to gain market share. I insisted on air brakes and Freightliner threw in the air ride rear axle for FREE!!! Cool huh!?!



Unfortunately my bus is one year too old and has the old style Allison in it, no lock up torque converter. Alas, I can't install an exhaust brake which is needed because the thing freewheels so easily.



I consistently get 9. 5 mpg with country side driving. A set of rv275's will soon be installed in the quest for better mpg's.



Trent

 

[barbwire]

Originally posted by redbadge

You can see the bus I own in my sig...



I ordered it with the Cummins ISB (24 valve) because I already owned my 1989 Dodge Cummins and loved it!



The cool thing when I ordered my bus was that Freightliner had only been in the bus chassis business for one year and they were pushing to gain market share. I insisted on air brakes and Freightliner threw in the air ride rear axle for FREE!!! Cool huh!?!



Unfortunately my bus is one year too old and has the old style Allison in it, no lock up torque converter. Alas, I can't install an exhaust brake which is needed because the thing freewheels so easily.



I consistently get 9. 5 mpg with country side driving. A set of rv275's will soon be installed in the quest for better mpg's.



Trent

For a 66 pass. bus,9. 5 mpg is pretty good , is'nt it? Man that is about what my measely 1 tn. reg. cab makes!

 

[ThrottleJockey]

Wayne!



When ya' gonna put a TST Powermax in that bad boy and have all the kids lookin' like this

 

[amsoilman]

Well Throttlejocky,



The last bus I drove had the 12V engine, and I did put a plate in it, but I think the Powermax would be too obvious! The present one does very well, especially on the hills!



Wayne

amsoilman

 

[blacksheepdiesel]

barbwire,

Considering the 17,000 empty weight and the numerically high rear end (don't know exactly what it is) I think 9. 5 mpg is pretty good. The frontal area on the bus is what kills the mileage.



ThrottleJockey,

I have wondered if a box designed for the Dodge Cummins 24v would work on the Cummins ISB originally installed in a different make. My guess is no??? I would think the ECM would be different.



Trent

 

[blacksheepdiesel]

To answer my own question,



Yes, the TST box will work on the ISB! Straight from the horses' mouth.



Big_Daddy_T,

When ordering a school bus I was given the choice of three premium engines (Cummins, Cat, Navistar DT466e) OR a non-premium engine, the Navistar T444e! That always stings the Ford guys pretty hard!



Trent

 

[WadePatton]

Kids these days!



When I rode a bus the powerplant of choice was the 318, yeeeha---yawn.