12.7 detrion compared to 03 cummins isx
 

Looking to buy.. but dont know which one to get.. anyone know?

help:D

Of those 2 choices, I'd go Cummins.

Otherwise, get a Cat.

I guess you mean a 12.7 Detroit?

The Cummins ISX is a 14 litre, so a larger engine than a 12.7 Detroit and will have more torque (power) and be better for climbing hills under a heavy load. On flat terrain the smaller Detroit should get better fuel mileage. If you are going to run a lot of mountains, you WILL want the stronger engine.

The Cummins has a great reputation, but when it does need a repiar, the parts are going to be more expensive than the same part for the Detroit. Also truck mechanics hasve worked on so many Detroits, because they are so common, that they are more likely to diagnose and repiar problems on a Detroit faster and more accurately than a Cummins. I currently have a Cummins, and I like it, but I think a 14L Detroit is a very competitive product.

Cat is getting out of the truck engine business. Their recent engines have a reputation for lots of problems, parts are far more expensive than Cummins, fuel mileage is the lowest of the three, and they cost the most to buy.

it all depends on what you want to do. the 12.7 has amazing milage sounds pretty good. on flat ground i'd say detroit. pulling weight and hills isx..


comparing the ISX to the 14l detroit.. hands dwon the ISX. i used to run a 400 ST isx and we also had 435/500 detroit 14.9 and hands down the isx would run circles around it. the company i work for now i drive a 515 14l detroit every day.. and i HATE it. runs like crap.. great power... when the egr isnt messing up.. smokes worse then a steam locomotive.. and sounds like a coffee maker.

Gearing can play a much more major role in pulling then HP alone.

Wow, that 515 Detroit sounds like it has serious issues! What year is it? I think just about every maker had big problems with the 2008 models.

The last Detroit that I owned was a series 60 12.7. It was a good engine but did have an oil leak problem. I think that every Detroit that I have owned has leaked oil. The series 60 isn't usually as bad as the older engines. I have never owned a Cummins, but have driven several different models over the years. I prefer the N14 over the ISX. I think they are easier to work on and are definitely a strong engine. A friend of mine has an N14. I think it is a stronger engine than the ISX. I believe CAT still has more torque and can out pull the other two. Of course, my friend with the N14 says the same about his Cummins.

I would not worry too much about the engine as long as it is a good truck and checks out. You should get good service out of any of the three brands. Although I have never owned a Cummins I would buy one if I found a good truck that was in decent shape and that I could get a good buy. If I had a choice between two identical trucks and one had a CAT I would choose the CAT.

Agreed. Gearing is everything. The right tranny/rearend combination is as critical as the engine specs.

The 12.7 Detroits have a good reputation for fuel mileage, next is Cummins, then Cat.

The Detroits are easier and less costly per repair on average than the other two. A Cummins usually has a good cost per life cycle ratio though. Cats are great engines, but over the life cycle, they can sometimes end up costing more to operate than the other two.

Cats and Cummins are great low end torque engines and will pull hills better than the Detroits. But, you will pay for that great pulling power over the Detroits in fuel. Nothing is free.

You didn't mention if the engines are pre-egr. If that 03 ISX is a pre-egr engine, then it would be the better overall choice. If it is not pre-egr, and the Detroit is pre-egr, then the Detroit is the best choice.

the 515 i'm talking about is a 06. i spent all f-ing day at ryder today with it. on a rev now it starts blowing grey smoke out of no where.. it sucks! now the 435/500 i drove i loved.

i personaly am a cummins man threw and threw.. but.. the detroits are great on fuel. if i was going to get a "new" truck i'd get a glider with a n14. n14. 3.55 rears, 13 speed. thats just me tho.