Help me compare these engines: Cummins vs Caterpillar

need more information then that. What Cat engine are you looking at? what purpose?

 

I have a cat c-15 ©500 hp eaton fuller 10 @1650 ft lbs torque and 343 rears (freightliner columbia 06) get 6 mpg if I run at 64 mph and gross 70,000. Any thing more fuel milage tanks and the cat has a few issues to be aware of...

 

what kind hp are you needing. the c-15 can put down some serious hp but does have mpg issues, specially if its now the right set up.. I dont know much about c12/13 but from what ive read here
they are not long lasting motors

 

ISX will have EGR/cooler problems and failures, turbo problems, and things related to the EGR system.

 

The cat will be the better motor depending on the type the acert motor has had a bad run from what I have seen though. But as CAT no longer make a road engine (I heard rumors they are going to again though) the cummins motor has had a huge increase in new trucks I have not driven with an ISX but if it is anything like the gen 1 signature motor it will be a good thing. We have an ISX 550hp in a kenworth k200 it has done 25000 k's (15500 miles) and the driver has nothing bad to say about it. I personally have found that the CAT motor is better on fuel. It is a hard one to pick and mostly personal preference I think. Have you concidered Detroit? They make a good motor nowadays to take some of the market left open by CAT. It also depends on the driveline (diffs and gearbox) behind the engine and the torque zone of the different engine your local dealer should be able to provide information on what to run with what motor. Try the cummins if you don't like it trade it at low mileage.