C12 - 430 HP or 480 HP

Holy crow!!! Man that's a lot of hours. I wouldn't touch that thing honestly. Just drive it. You start dinking with it with that many hours it's going to lay an egg for sure. Wait till it craters then rebuild it then after its fresh , feel free to play a little.
Just my 2 cents.

 

Cats RV files are designed for low load applications, if the engine load factor goes over a certain limit the engine will derate as the ECM knows its being used in the wrong application. Aftermarket tune would be the best way to go but at 43000hrs I would be looking at a rebuild first.

 

i have 642k on it now with 25k on a tune doing air mile work. I have a lot more idle hours 47000+ and that was a year and a half ago. so it has more now. it has always used oil, I go through a gallon every 4k miles and that is about a month of work on a average of 50 hours of run time a week. It idles all day with what I do.

Im due for a rebuild eventually, just a matter of time. Honestly if it was going to blow up it shoulda done it already, I weigh over 90k pulling some hills around the river here. It gets a workout but does it very well.

I really want to get it dyno'd but i live a hour north of the cities so I'd have to make a special trip. Maybe sometime ill get it on the rollers, it would be cool to see what it makes.

 

I have been thinking about doing the same thing to my c-12 i did an in frame on it at 983,000 miles and have another 100,000 on it now. But i have been wanting to talk to some one who has done it on a c-12. I am at 410 hp now and it is a little weak for me. It does get good fuel mileage now though and i don't want to lose that. Did you notice any difference in fuel mileage at all and is it still working good for you after a year has gone by?

 

Wow, thread back from the dead. How do your guys' c12s run stock power wise? Drove one a while back in a single axle shaker with a 4 car trailer. Did ok once it was wound up, but was a real dog down low. This was set at 410hp. Owner is looking to improve it, but I don't know if something may be out of whack on it, have nothing to compare it too

 

My c12 is 410 hp and i haul a 48' flat bed with 80,000 to 84,000 lbs. It takes a while to get up to speed and i have to down shift more often. I have another truck with c15 at only 400 hp and it out pulls my c12 pretty easy. I did not notice it much until i drove the c15 for a while and then went back to the c12 and one morning i had a good head wind but not much to worry about and after going the first 10 miles or so only doing 55 i pulled over to see if i had a brake froze up and dragging but it ended up just being my weak c12. Another guy drove it for me later that winter and he did the same thing, he thought something was wrong with my truck and pulled over to see. LOL

 

a stock c12 empty will barely pull away from a 40k lb loaded tuned c12. 600hp vs 425ish is a big difference

 

My Cat C-12 has a broken spring on valve number 4. Is it worth fixing or should I just replace the whole engine.

 

im thinking it the reason has to do with duty cycle. a 30k lb rv will operate at max power for less time than a 80k lb semi tractor. engineers probably decided that the engine could safely produce 480hp for say 8 out of 10 mins before needing a cool down where it could operate at 9 or 10 out of 10 mins at max power and still be safe.

 

Broken valve springs can easily be replaced in the truck provided the valve did not hit the piston. Whether or not its worthwhile is up to you. Engine hours/condition. Truck milage, ect