Detroit DD15 455HP or Cummins ISX 450HP

Don't know if this will help or not but I drive Cascadia's on rotating weeks with both engines. Surprising to me, the Cummins gets better fuel mileage and has more torque. Up until October last year, I had my own trucks for 16 years and have always had Detroit's for the most part. Did have 1 truck that had an ISX in it but not for long. Since October I drive 1 truck for a week then the other for the 2nd week then switch back. I still prefer the performance of the Detroit, the Cummins has a higher idle point, but I was shocked with the comparison.

 

post 2013 isx15 has better mpg but burns more def than 2010. Has less breakdown.

 

Detroit 100%! Every time I look at a broken down Semi on the Interstate, and with the hood open, I always see the red Cummins engine! If you find the right EGR mechanic, you will have a Detroit forever. Trust me on that!

 

I have a 12.7 Detroit, after the right people worked on it, no Cat, Cummins, Kenworth, Peterbuilt, Western Star, can catch up to it. I asked the technician to bump the speed up to 95 MPH and from 455 horse power to 500 and it's funny seeing these monster over the road Peterbuilt's with all the loud stack trying to catch up to the Freightliner Century on Florida's back roads where there's no Troopers and see how those monsters struggle to catch up to little 12.7 Detroit. I had to stop running like that after a Tropper somehow sneeked behind me on the Courtney Campbell I- 275 over the Gulf of Mexico and when I got out, he asked me for medical card, registration, he was going to make an entire inspection on the truck even the engine by a state inspector, well after a conversation about safety, he gave me the license back and warned me if he sees me running like that again, my license is history. But again, Detroit Engine is the best Engine in todays market.

 

12.7 Detroit. Best on fuel. We had century with 12.7 detroit with 3.42 rear axles. I'm not that into high hp like 1000 hp. If CAT, i'll go to 550. If detroit, i'll for 500. detroit are cheaper with parts compare to cat.

 

100% correct, I bought an engine starter for that engine at the dealer and that starter was $269 reman. A steering gear box for $581. I saw a driver asking about a Peterbuilt part, smaller than the palm of the mans hand and the salesman says, that part is $350 and best I can do is $325. The man was so shocked that he relented and paid for it. Detroit and Freightliner were built for the working driver.

 

Also on the hunt for a used truck and have note that the DD15's are priced higher than similar mileage isx motors

 

I was in your situation year ago . I bought a dd15 epa10 Cascadia. Now if you will buy a isx check the serial number of the engine. If its earlier than 79608640 don't buy it. You will have a big problem later( cylinder's shim problems, repair cost about $15). Also check to see if the high pressure pump is updated. if its not stay away. There are ceramic parts in the pump and they get broken. the whole fuel system must be repaired after that. Expensive ! About $12-14K ! On dd15 you will have dosing unit, metering valves and some sensor problems, not expensive repairs. If you need Cummins ISX engine TSB about Cylinder shim I can send it to you and the engine serial numbers are on that document so you will see whas the problem and what will be done on those engines.