Does anyone else have a truck like this?

Jake I am/was a tech for many years, while I agree that the engine manufactures were thrown a raw deal in having to ramp up emissions in such a short period of time, they of all people had a much better and a much more unified platform to speak from to the Gov. about what could be expected and what was feasible.

Instead, they all bowed down to the know-nothing pencil pushers in Washington, put out a somewhat untested product, and then passed all of the problems unto their customers, and consequently, put some people out of business.

Don't feel bad about injectors, we service our trucks EVERY 25,000 miles, this includes ALL THREE FUEL FILTERS, and we have replaced injectors in half the trucks, some as low as 150,000 miles!!!

 

I am thinking the high fuel temp is killing the injectors ? Know the fuel is way hotter then it used to be.

 

yet you continue to run a castrated truck and on the lowest power setting.


So do a "test". Take 2 trucks and turn them up to full power.


Oh wait, their YOUR Trucks. You will do what you want. You have nothing to loose at this point and every thing to gain. Yet you refuse to acknowledge that someone else MIGHT have a good suggestion for your.

I wish you the best of luck. You obviously don't want to listen to others suggestions.


Just curious.

What's the soot level in your oil samples?

 

In essence, you are lugging the hell out of these engines. It's bad enough, you do so at such a low RPM, but fleet managers/owners and those "that know what they are doing" feel the compelling need to castrate a truck to get mileage.

It hurts you, it doesn't help.

Supposedly you need 11 HP for every 1 ton of weight just for getting to cruising speed. Just something that's been discussed with me since I got into trucks since 1990. That would mean for a traditional Class 8, that would be a 440 hp engine. HP only says how fast you are going to go. Torque is going to get the work done.

How your driver operates it will be as critical as the condition of the tuning.

Add in the junk for emissions, you are choking your economy even further. Gets back to volumetric efficiency. Already low from being an reciprocating internal combustion engine, killed even further by trying to cool the cylinder in the compression cycle to reduce NOx.

Will turning your engine up to 450 help? Most likely. I think you'd be better off turning them all the way up.

Would you use a Chevy S10 pick up to pull a 4 horse trailer? If not, then why are you trying to do essentially the same thing with a Class 8 rig?

 

You ask for help, get good suggestions and then belittle people for making them to you. You have SEVERAL threads related to this started and people are telling you to turn your trucks up and you continue to question how or why that would help you.


Read your oil analysis reports. Your soot is likely in spec, but still high in spec. It's telling you right there, the engine is lugging. I saw that same thing on my engine and when I turned it it up AND gave it the fuel it wanted/needed, both my economy AND my soot levels improved.


You implied that since I only have one truck I need to worry about, I can't understand what it is your are dealing with in your fleet.

A truck is a truck. In a fleet of one or a fleet of 50. We both worry about the same thing. Reducing fuel AND maintenance costs. And that is a balancing act in and of itself.

I won't go into your comments on controlling your drivers with GPS and EOBR's.

 

Detroits need more RPM than a Cat. Buddy is running a C15. He can cruise in the hills at 1400. I have to be at 1475 to 1500 with my S60. Even at almost 100 RPM higher, I am killing him on mileage at almore 1.5 to 1.75 mpg better economy.

To the best of my understanding, it has to do with the design of the crankshaft and the blackmagic voodoo that happens with a longer crank stroke.


We are stressed to run these engines at lower RPM's. I had a struggle with going back up in RPM. But when I started to run 1475 to 1525 from 1400-1425, I saw a big change in my fuel mileage.

 

OK, back to what I said, IF more rpm equates in your mind to better fuel mileage, than why is that Pete doing just opposite? The Pete BTW is running a Cummins, not a Cat, if anything it SHOULD need to run more RPM, it IS a MUCH smaller motor.

 

Power curves....

You don't run it at the bottom. You run in the middle.

CAN you run at the bottom? Sure. But you won't have the "sweet spot" dialed in. I run on RPM and what gives me best performance AND economy. I had to bump my cruise speed to 1450-1475 to do that from 1400-1425. When I get into the bigger rollers like across I-80 in Iowa, I even go up to 1500-1525. I hold a constant steady speed and I am out of the hills faster. If I let it run down to 1400-1425 RPM, I actually have to start grabbing gears to make it up over the hill.

And those are my actual dyno runs from when Rebel127 ran my ECM out in PA last December. My economy is 6.5 on winter fuel now that my overhead was run. That's also running against heavy winds and also over 70K gross.