I have been monitoring my regens and noticed last week it went into regen mode (passive) while driving at 80% Normally 100% is the trigger. So i have done a manual regen in the driveway once. I dont care for the loud and high rpm's generated thinking it harms the engine with so high rpm's for 30 mins. Is this true? Also would a manual regen give me a better regen burn than the passive and that maybe why it triggered at 80% thanks Jeff

 

A passive regen is not something we have control over... once the running temps get up a passive regen is just what happens with normal driving, and can happen anytime between 0 and 100% DPF. If you are talking about an active regen, then I have seen mine go into a regen at 95%, and recently, I believe it went into a regen when the trucks DPF% was in the mid 80's. Besides the DPF% reaching 100% though, mileage can also force a truck into an active regen. I assume when you said passive regen, you meant active regen, and maybe it was the mileage limit that kicked it in.

As for a static, or manual regen, I see no reason why this would harm the engine. There can easily be just as high RPM's when driving down the road pulling a camper, and for hours at a time.Some people will open the hood to help disperse heat, but IIRC, the manual states that this isn't necessary. And far as a manual regen being better than an active regen (or vice-versa), I can't answer that. Maybe someone else can chime in on that... But I would imagine that a regen is a regen, assuming that they are fully completed, and one isn't "better" than the other.

 

I've put almost 400,000 miles on 6.7L engines since 2011 when they came out. I have never done a manual regen.
Trucks have all operated just fine for me just letting them do what they are programmed for.

An Active Regen will take place when your DPF filter load reaches a certain threshold and you are up to operating temps. The trucks also seem to have a maximum distance between Active Regen ( I've heard people say that max is about 500 miles) So even if your DPF Soot load is low, you will still go into a Active Regen when you hit this milestone. Say every 500 miles. An Active Regen means your engine is injecting extra fuel into the exhaust to increase the EGT to high enough temp to burn the soot. Usually an Active Regen will see EGT temps around 1100°. A manual regen is a Active Regen that is manual started. It does inject extra fuel.

Passive Regen means just that. The DPF will passively burn off soot when ever you have sufficient heat in the DPF. It does not Inject extra Diesel Fuel to help the DPF get hot enough to burn the soot. The 6.7L Coffee Table book says Passive regens happen anytime your EGTS in the DPF exceed 572°. So for my 2020 F350. I can cruise down the freeway at 70 mph and see EGT temps in the 500-550° range. So no passive regens are happening. But if I hook up my horse trailer and tow it at 70 mph, I'll see 750-800° on level roads and as high at 1300° climbing 7% grades in the mountains. So passive regens are occurring almost continuously as I tow. In fact, I can leave home at 50% Soot load and tow my horses 350 miles to St George at 70 mph on I-15 and never see an Active Regen and arrive in St George with 5% soot load. And I may see an Active regen on my trip home ( triggered by the 500 mile limit) while I only have 10% soot load. Luckily any Active Regen under that circumstance is fairly short lived.

 

Over the weekend, on a drive home from Wyoming my truck went into an active regen at 65%. It hit the 500 mile limit. The regen went down to 0%. I use the Trip B odometer to track the number of miles since the last full regen so I have an idea of when one is likely to start.

I've never seen my truck do a passive regen that resulted in the DPF % going down more than 5%.

 

ok thanks, Today I was at 70 % Truck went in to active regen and completed by the time i got to work to 0%. So I will guess the mileage is the trigger lately as the previous reply's stated. I have not been watching the mileage to compare but i will rest it today to compare. thanks for the info. Jeff

 

I can passively regen and keep the soot % at zero towing heavy.

My 2013 and 2020 could go from Maryland all the way to Arizona, about 2200 miles without a regen while towing.

They fixed that for 2021. My 2021 will passively regen and keep the soot at zero % but it regens at 496 miles every time.

So depending upon the year you may exceed the 500 mile limit.

 

I use the Edge CTS and it will display Average Regen Distance. I see this number float between 360 and 450 miles. So most of the regens are triggered by Soot load and not the 500 mile max