CAT tuning information/help

I’ve been reading the forums for a long time, and I’ve finally gotten to a point I need some help.


My situation:
-Freightliner M2 with a C11+10spd OD.
-3.73 rears, 455/55r22.5 auto-inflated to 95psi.
-avg speed between 55~60mph=1350~1425.
-I pull hazmat tanks regionally on dedicated acct.


Originally rated at 335/1200, a CAT dealer flashed it to 370/1450....which I couldn’t notice any difference. I run out loaded (73k) and back empty (29k), on the same route every day. Rolling hills mainly except one where I have to shift out of OD. It’ll lug down and hold/pull a grade the same speed as it did as lower ratings, as well as fight through any surge that may happen just the same. Never runs over 200*F.

Fuel economy:
-Empty, avg 7mpg.
-Loaded, avg 6mpg.
-No idling (eAPU), rare PTO use.
-March IFTA was 6.34.

Here’s where it gets interesting and I get confused: it was flashed with a C13 500/1700 file last year, and that’s what’s in it now. It feels exactly the same as it was at 370, and fuel economy remains unchanged. I’ve driven other engines rated less, in combinations heavier than this, and they’ve both felt faster and got better economy.

I haven’t dyno’d the truck, so I’m not entirely sure what it puts down. Its gear ratios are horrible (needs a 3.08 out back IMO), so I shouldn’t be spinning this thing higher than 1500rpm (which is 65mph) right? Seems to tank the mpg.

Is there any issue with the ECM running its bigger brothers flash file? Can it actually run that file? Is my fuel economy lower on the C13 rating, even if power demands are the same, versus a C11 flash? Are there any differences in camshaft or other things I should know about? Could the timing be off because of the difference in crank stroke, reducing power and efficiency? I don’t know what injector codes are programmed in (if applicable). Could it be the stock fuel injectors I have can’t put out any more or enough fuel? My fuel pressure is high, and the turbos are the same as the C13, so those shouldn’t be limitations.... I have the Cat ET print out, and nothing therein seems to jump out at me.

ESN: KCA11436

....Help!

 

Anyone?

 

Yeah, I have heard that same argument. I usually feel the same. But the C11 and an ISM that I run in the fleet are changing my mind. But also, check this link out. I found this the other day. So far, my C11 has been dead-on reliable....just not efficient. Not that CAT is known for mileage like a DDEC3 12.7 or newer DD15/DT12 combo.

https://www.truckinginfo.com/156963/ploger-transportation-pushes-10-mpg-with-a-far-from-typical-powertrain-spec

 

The 3.08 would be for cruising on flat ground or when empty. I’d run in 9th/DD when really pulling something serious. I can already lug it down to 1100rpm in 10th and hold 45mph on the way up all but the steepest grades I’ve ever put it up against without overheating or whatnot. that’s around 1600rpm in 9th @45mph. More importantly, on the low end, it would make 1-3 not as ‘useless’. They’re exceptionally short now and barely useable with 3.73s, I usually only use 1st when loaded on a steep grade (over 5%). Otherwise it’ll do more than fine starting off in 3rd loaded/4th empty/5th bobtail. Original clutch and driveline.

This thing has given me great service over it’s life, but the efficiency difference might’ve cost me upwards of 30k in diesel over that same timeframe; considering I keep getting told fleetspec 450hp DD15/DT12 Cascadia sleeper trucks (+5000lbs tare weight) are getting 7.5 loaded and 9-10 empty at 65mph.

I already have the Donaldson on there, would I gain much going with a true straight-pipe?

Here’s a picture, don’t roast me too hard haha.