Emissions Maintenance on X15

Only advice I have. Get a scan tool or cummins insight software so that you can diagnose issues early. And buy a warranty that covers the time you plan on owning the trucks, you will recuperate the cost.

The dpf and def filters will need replacing at or very near their recommended interval. Differential pressure sensors carbon up and need cleaning / replacing. All things emissions related will work until they do not. Quality control with sensors is horrible, and some are designed to fail ... like the def quality sensor. Def pump, def heater.

Search Rawze on google ... tons of good cummins info.

 

DEF filter every 100k miles, inspect DEF doser and 7th injector and clean if needed.
DEF / Urea Filtration | Cummins Filtration

I'd remove the DOC/DPF every 300k-400k miles and have them baked. It is probably a good idea to do the EGR cooler at the same time. If you get a lot of idle time or it's used in heavy duty applications a lot, I'd do it closer to 300k. I'd also clean up the venturi mixing pipe between the EGR cooler and intake manifold.

Top off the DEF pretty often, don't wait until the tank is low or empty. If you get a bad batch of DEF, it might not throw a code if it gets mixed with enough good DEF. You would have to get several bad batches in a row for low quality codes to show up as a result of bad DEF. I have less issues with large chain truck stops than the smaller ones with bulk DEF.

The SCR system and the DPF system are separate, even though they're both related to exhaust. SCR controls NOx emissions- it's starts with EGR to control temperatures, flows over the catalyst coating on the DOC, gets DEF sprayed onto it, then flows over the coating in the SCR box.

The DPF system is for the soot, it is measured by the difference in flow before and after the DPF filter, which is then compared to data to determine if it's accurate or not. So even if the DPF isn't full of soot, it can be tricked into thinking it is, by a blockage or leaking of pressure somewhere else in the exhaust stream. When the filter thinks it reaches a certain fullness, the truck will try to convert the soot into ash by injecting more fuel into the DOC. Usually it's passive and happens while you're driving. If the truck can't maintain high enough temperatures for a long enough period, the truck will asked for a parked regen. If the truck does not complete the regen, you'll need to determine if it's too full of ash(or bad flow rate) or if temperatures are not getting high enough to burn the soot.

If you maintain these systems, you can all but rule out things like a blocked DPF or low quality DEF when it comes time to troubleshoot them. It's not always as simple as that, but that's a crash course in what you're up against.

 

OP will probably go off hours rather than miles. Usually takes a few years just to get even 300k kilometers on a truck in her applications.

 

I was just looking at the service intervals for the X15. You'll probably be in service range to have the DPF cleaned/exchanged every 24 months give or take.

 

My uncle has owned 2 or 3 T-800's with the DEF tank. He swears by getting as much aftertreatment warranty as you can and he trades them in just before the warranty expires.

The thing I hate about the aftertreatment is that if the turbo goes boom, instead of cleaning oil out of the exhaust pipe you're cleaning or replacing expensive catalysts now too. Bad enough paying $6k for a turbo but now you've got to fork out a few thousand more for the contingent damage to the aftertreatment system if its off warranty.

 

Just have someone delete the system lol