ISX vs C15 fuel economy (and 379vsW900)

[Camstyn]

Thanks for all of the info guys, it is very much appreciated. After a lot of reasoning I have pretty much decided on a pair of Western Stars (4900EX or lowmax) with the Mercedes 450's. I think it is the smartest choice. While it would be great to drive a 379X or a W900 this is the best compromise for me, and I think the 82" bunk will be more than accomdating.
The salesman at the WS dealer is trying to sell me on the leftover '05 lowmax with the 515 detroit that was used for truxpo, it's got everything you can put on it and it's a hell of a price but I think I'd rather order one with a mercedes and it will pay out in the end. From what I've gathered it will be at least a 0.5mpg advantage which is significant after you add it up for 5 years.

While I'd love to go with a loaded 379x with a Cat, the Western Star Lowmax w/ the Stratosphere just plain blows it away for practicality and it's just more suitable for me. If fuel economy was not a big deal I'm almost certain I'd be going with a Pete but I am think the WS is the best trade-off.

Now is the waiting game to see if I win the bid tender. I've put the wagon before the horse here so I hope it works out but if it is awarded to someone else, best luck to them, I won't lose any sleep over it.

 

[Brickman]

I run a 96 T600 C15 set at factory 435 HP. I spend my fair share of time in the left lane and run 130K or more miles a year on it. Worst MPG was 4.8 mountains, heavy load, lots of head wind and idle at night.
Best was 8 bobtail. Average runs from 5.5 to 6.4
And I do not have to run it at 1900 RPMs like the ACCERTs, 1300 to 1500 climbing 7% grade with 48K lbs.



After all the horror stories I've heard about the ACCERTs I will continue to run a non EGR engine.
Even tho the new trucks look sweeeeeeeet I would buy a 78 to 80 W900 B model and restore it if I had to. That vintage all dolled up look GREAT!!!

 

[Pacific]

I think I would stick with a standard 4900 Series over the the lowmax you really don't want a truck with no clearance. The 4900SA would be a good choice for the 53' trailers you want to pull.

Are you getting the Fuller 18spd behind the mercedes with the extra gear splits you really will beable to progessively shift the truck to get the most out of the engine.

 

[Camstyn]

Yeah I think you're right about the lowmax, there is a lot of wildlife on that road and I wouldn't want something so low that roadkill will hang up on it.. I would definitely go with the 18spd, I think on that road you can't have too many gears.

 

[Iron Horse]

Not so sure about the Mercedes engines yet. Everyone I have ever driven feels like a lot more power then what they are rated at, and seem to run very good. Have no experience with them in an OTR setting though, most of them around here are either dumps, pulling belly or side dumps, or are hauling hog or cattle feed. Have heard nothing but good things from drivers as far as performance.

Parts are still very scarce, and you can only have the engine worked on at an authoriezed Detroit/MB shop. My cousins truck dropped a piston at 19x,*** miles, but the truck delivers feed, so it has a lot of time at high idle running the unloading augers. Usually down time is dependent on parts, as most failures I have heard of are usually minor.

 

[Pacific]

Ya I'am not so sure on the Mercedes engines aswell but I guess its a risk you gotta take if its under warranty its not so bad.

 

[Camstyn]

I spoke with a fellow yesterday who has a 450horse MBE4000 in his Freightshaker Columbia, he's had it for two years now and is almost at 250k miles, never been on a hook. Excellent fuel mileage too.. I think I would have to hear some real first-hand horror stories to sway me away from that motor, it sounds like a good one. I know that parts are scarce but with the number of these things on the road I'm sure that it won't be an issue for much longer.

At the same time a buddy of mine hauls 140k lumber wagons, 2005 long nose Pete w/ a 550 Cat and he says he averages 6mpg, but he's only loaded one way and empty the other. I know he drives the balls off of it too so I was surprised to hear he was doing so good on consumption.

 

[ndurbin]

The DDEC4 (I believe thats what its called) that controls the MB engines in the Freightliners is pretty neat, I imagine the Western Stars would have it too. It logs idle time, when the engine is on or off, driving MPG (no idleing), total MPG (including idle), and a whole lot of other things. I'm by no means an expert but keeping your idle time down well help your overall mileage, that was one problem the trucking company I worked for had, to much idle time in their OTR trucks. Their also easier to do routine maintence on (filters and such) as their easier to get to. Ya do need a good set of metric tools for the engine tho if your going to do any of your own work.

The trucking company I worked for ran all 4 four eninges (CAT C-12s, Cummins N-14s and M-11s, Detroit S60s, and MB 500hp). All the MB equipped trucks had atleast 13 speeds and one or two had 15 speeds, everything else had 9 speeds. None of the drivers ever seemed to complain about any of them. The guys who ran the MBs did like them tho (but they where the highest rated HP wise).

Not sure any of this may help but it's what I remember from when I was working their.

Nathan

 

[Deezle1]

ive driven a MB powered rig. i hear good things too, from a few trucker buddys. one has a detroit, one has a MB, and the other has a built up cummins. Out of all of them (they have driven each other trucks) everyone says the MB has the smoothest ready power. The cummins guy's truck is an animal, it has KATETR1 on the license plate. he pulls hills faster and easyer than almost any truck ive seen. The detroit guys truck runs very well, has 400k on it, everything original. MB has a great reputation in the diesel industry, and from my experiance of driving my buds rig from Boston to Buffalo (the MB) i think its just great. i only had a few decent size grades tho.
just my .02


Keep truckin,
Dom

 

[Skipper]

Anybody look into a 660 cat? Twin turbo from the factory. So far have heard good things about it.
ISX heard run hot. They have egr and run that through an after cooler. I don't know the horse rating is. But don't think its over 600 hp.
Personally I'm not crazy about the metric trucks. I'd buy american.