What engine with DEF is having the least amount of problems?

get a cat truck like a ct660 or ct630, they don't have egr systems or scr systems so no dpf and no worries of filling up that god #### def crap haha, also the cat blocks are amazing, comes with 475 or 550 cat option, I recommend the 550, and if possible the cx35 is absolutely amazing, I got the opportunity to test one, pulls great, along with the torque converter lockup is nice when you get in 6th gear at 2000 rpm, kick on the lockup, feel the truck surge forward with power, Its boring as #### but really great for heavy hauling, city driving, backing, doesn't do that dumb jump thing the Eaton's do when the clutch slams out in reverse, got a torque converter so no worries of clutch replacements, I recommend doing a pittsburg power box with it, get up to 750hp along with that transmission would have just the most smooth, consistant, beautiful, accelerations you'll find.

 

Cat trucks are decent. The only major downfall is lack of diagnostic support. Not all Cat dealers have the software to connect to them as there isn't many Cat trucks on the roads (only seen 2 or 3 regularly in my region, all owned by different companies). Our shop has tried to connect to the truck with Cat ET and apparently it will not connect. Was told the truck was sent to the International dealer and the International diagnostic software won't connect either.

 

I didn't know the epa allowed any truck maker to make an on highway unit that isn't required to have all the egr dpf scr+def .... thought they have the off road stuff in the cross hairs now

 

I had a 2013 Western Star with a DD15, I never had a problem with it. Put just over 325,000 miles on it. Now have a Cascadia with a DD16.
Seems to me some of the issues with the ISX are related to extended oil change intervals. Don't do it. Four of the company trucks with ISX had extended oil changes, all were rebuilt before 225,000 miles. Only one made it beyond 400,000 miles before being traded off, that driver always did oil changes pretty much monthly.

 

The only thing my 2013 mack keeps having issues with is the ac system. It just broke 426k last week. Other than some brakes, a clutch adjustment, and tires, service logs show nothing but the normal pms and an ac compressor

 

Ya, I've read a few fuel pumps giving out and after a bunch of miles the DOC catalyst gives out so the whole One-Box has to be changed out.

 

I just wanted to comment on the ISX's that need to be overhauled around 200K. These are mostly 2013 model year engines with defective cylinder liners. These are allowing too much blowby and oil consumption in addition to piston ring carbon packing. Here is a link with further detail.
http://www.thetruckersreport.com/tr...cummins-4-corner-score-5.256270/#post-4131526
Other than that, I can't comment too much on recent Detroits, but ones from a only a few years ago seemed to be very reliable. ISX is ok too. The problem with ISX and the aftertreatment is actually the fault the of the OEM. Cummins only makes the engine, DOC/DPF and SCR component parts. It is up to the OEM to manufacture, install and route the wiring harnesses that connect everything. So far, 90% of the problems I see are wiring related, and therefore OEM related, not Cummins.

 

The ISX 15 CM2250 had a bad piston ring design that allowed carbon to build up between the rings and score the liners. Many had to be overhauled shortly after the 200 mark.
My truck was built in October 2013 and has the newer CM2350. I'm told that it has the updated pistons/rings that don'thave this problem. My truck has been virtually trouble free it's been in the shop 1/2 a day total. To be honest, I was planning on having more trouble with it than I've had.
285k 5700 hours.

 

They don't. The cat truck is not allowed on highway. You see them mostly at mining sites and military applications.