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"Soft" regen? versus "Hard" regen?
Can somebody fill me in here?
 

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2019 Titan XD Pro4x Cummins
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In the heavy duty diesel arena there is two kinds of burns, passive and active.

Passive is when the engine is being worked hard enough that the exhaust gas temp is naturally high enough to burn the soot into ash.

Active means the DPF has reached the storage limit for soot and must raise the temperature of the exhaust gas through other means, such as injecting fuel into the exhaust to bring up the EGT.

Kind of dumb on Nissan/Cummins part not to follow the same naming convention as heavy duty engines.
 

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Yeah, that's what I was thinking too.
"Soft" is just the normal burn off during heavy loads. Passive regen.
IOW nothing special, no higher revs, no higher exhaust temps, *other* than that required by the higher loads.

But the video is showing a "soft" or passive regen how?
Are they just hauling load up a hill at 1000 rpm or what?

I don't see anything happening?
Maybe it's a joke?
 

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It's in park so it's not moving. The RPMs are slightly elevated but wouldn't think it's enough to significantly heat up the exhaust anytime soon. I guess we'll need to wait for Nissan to explain.
 

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I don't care about how it does a regen; it's a federally mandated system and depending on what Tier level (<3, 3, 4 interim, 4 final) its categorized in - they are all very similar (whether it's a truck, tractor, etc.). I've had and have quite a few different things with emissions systems, from tractors with just DPF (no def) to trucks with full T4F systems. All have been reliable but I do have a couple tips to help them remain reliable:


-don't fill your def tank right full in the winter. DEF freezes at -11c. Keep it half full if you can. Ford had some issues with tank heaters going out because the tank was full and it froze. GM has had more problems with their design by not having it clear the lines after the truck has been turned off (instead relying on just heated lines). Out of the HD trucks, the GM def system is the worst (tank location, fill location, heating system, etc.)
-exhaust heat. This is something to be aware of when towing, parking/driving in confined spaces, and parking/driving in fields with dry stubble or grass (fire risk). The towing part revolves around the exhaust tip. Ford has a twin tip venturi that hasn't caused any issues (none that I know of). GM has the infamous trumpet horn pointing almost straight out the back. It's melted camper siding, damaged boat gel coats, melted through tow flaps, and even melted GM's own version of the "man step". The trumpet horn is not a good design IMO. Most people will have it cut off and a new venturi tip welded on and directed out the side (but you still have to be careful with the position in relation to the body and surrounding paint). Ram does have a venturi, it's located further up the exhaust stream and not at the tip. Never seen or heard of any issues.
-probably the most important part - just drive it normally! Don't worry about the emissions system other than making sure the system has def and the engine has the correct oil.


Benefits I already see in the Titan XD:
-it uses the same venturi design as the Ram.
-the def tank design and fill location is like the Ford/Ram.
-it actually has a def gauge, which is awesome


In conclusion, the Titan XD has all the best emissions design features and should be a reliable system. Other than the small-ish def tank, I have no complaints.
 

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The Ram Ecodiesel had some growing pains with it's regen system including clogging, limp modes, dealer visits, etc. There's no reason to assume the XD's will be the best of all worlds. I'd expect similar issues if not worse given this is Nissan's first entry in the US diesel pickup market.
 

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True - the ecodiesel has had plenty of growing pains. It's pretty much turned me away from buying one, even though the reported 34+ mpg (not US) is very very tempting.


However, the one difference here is this - Cummins designed the emissions system on the Titan and no doubt had a large role in calibrating the bcm software as well - that all gives me an elevated level of comfort.
 

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So....need help here, i was reading in the Titan owners manaul...the "Titan Diesel" and on pages 2-4 (11), 2-6 & 6-16 it says that we should get a message on the information display saying the vechile is in a regen.....i have 5k miles on my Titan Xd and got thru about 3 regens and have yet to see this message. Has anyone seen that mesaage when your truck enters an Regen? Just asking....maybe i need to check a setting.
 

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Yes, no messages just a bump in idle and a drop in mileage to about 8 and smell in traffic. Put hvac on recirculate and run it on the highway if you can. With my driving a mix of highway and traffic it regens every 24 hours of operation regardless of miles driven.
 
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