Fuel Additives for Diesels

Rickhansen

Well-known member
Will one of you kindly explain "regeneration" and "cleaning exhaust filter". I've seen "regeneration" mentioned and the other showed up on the dash while driving the last couple of days. The alarm cleared almost as fast as it came on. What little I've found so far suggest the "cleaning exhaust filter" as a normal function so long as it does not stay on. Is this correct?

Cleaning Exhaust Filter and Regen are the same things. Your truck has a DPF (Diesel Particulate Filter) that catches soot, hence why you see no smoke in your exhaust. Over time, the filter catches all the soot it can and begins to clog, like a vacuum cleaner filter. When your truck senses the differential pressure beginning to rise, it jacks up the EGT (Exhaust Gas Temperature) for a while to burn the soot. It disperses out of the tailpipe as a fine ash. When the filter is cleaned, the truck comes out of regen. On a 2011 or newer Chevy/GMC the EGT is raised by a 9th fuel injector behind the turbocharger. On older moder it is done by injecting raw fuel into the cylinders during the exhaust stroke. That had potential to saturate cylinder walls with unburned fuel that could seep past the rings and dilute your crankcase oil over time.

On my GMC, there is no notification of regen under normal conditions (wish it did) and the only things I've noticed is a drop in the miles per gallon, slightly higher idle speed, and a slight change in the exhaust sound at certain speeds.

None of this should be confused with Diesel Exhaust Fluid (DEF/Urea) and the SCR (Selective Catalyst Reduction) (on Fords and Duramax engines) which is a chemical and catalytic convertor of sorts that breaks down nitrous oxides in the exhaust gases. Dodge runs huge amounts of EGR to break down the nitrous oxides in a different manner, and do not require DEF (yet). That method has other drawbacks, as well.

None of it is infallible technology, but it is required (EPA), is difficult to defeat, and has been in use in various countries for some time. I've had no issues in 26,000 miles, except one flash update by the dealer for an updated calibration.

Hope this helps.
 

ncc1701e

Well-known member
Cleaning Exhaust Filter and Regen are the same things. Your truck has a DPF (Diesel Particulate Filter) that catches soot, hence why you see no smoke in your exhaust. Over time, the filter catches all the soot it can and begins to clog, like a vacuum cleaner filter. When your truck senses the differential pressure beginning to rise, it jacks up the EGT (Exhaust Gas Temperature) for a while to burn the soot. It disperses out of the tailpipe as a fine ash. When the filter is cleaned, the truck comes out of regen. On a 2011 or newer Chevy/GMC the EGT is raised by a 9th fuel injector behind the turbocharger. On older moder it is done by injecting raw fuel into the cylinders during the exhaust stroke. That had potential to saturate cylinder walls with unburned fuel that could seep past the rings and dilute your crankcase oil over time.

On my GMC, there is no notification of regen under normal conditions (wish it did) and the only things I've noticed is a drop in the miles per gallon, slightly higher idle speed, and a slight change in the exhaust sound at certain speeds.

None of this should be confused with Diesel Exhaust Fluid (DEF/Urea) and the SCR (Selective Catalyst Reduction) (on Fords and Duramax engines) which is a chemical and catalytic convertor of sorts that breaks down nitrous oxides in the exhaust gases. Dodge runs huge amounts of EGR to break down the nitrous oxides in a different manner, and do not require DEF (yet). That method has other drawbacks, as well.

None of it is infallible technology, but it is required (EPA), is difficult to defeat, and has been in use in various countries for some time. I've had no issues in 26,000 miles, except one flash update by the dealer for an updated calibration.

Hope this helps.

This seems to explain what I noticed and startled me the first time. I suddenly noticed a significant drop in fuel mileage as calculated by the computer. This drop lasted for 5 minutes or so then returned to normal. The next time I saw this drop I also saw the message "Cleaning Filter". The message only flashed on the screen for 15 seconds or so. I assumed this was some normal process in this truck, but the first time somethng like this shows up and with no real experience on diesels I was nervous. Thanks.
 

JohnDar

Prolifically Gabby Member
On my GMC, there is no notification of regen under normal conditions (wish it did) and the only things I've noticed is a drop in the miles per gallon, slightly higher idle speed, and a slight change in the exhaust sound at certain speeds.


That's about all I've noticed on my 2009, as well. Doesn't last long, either.
 

porthole

Retired
Regen should be addressed in your manual.
Anywhere from 1-5 minutes is typical. under normal driving conditions. If you are always towing you may never see the regen, because the is engine is working harder and taking care of the "regen" on it's own.
3-5 MPG drop is typical too.

So, light use, you will see regen and less DEF consumption and normal fuel mileage (for your truck)
Heavy use you will see less regen, maybe not at all, more DEF consumption and of course, your mileage will vary.

I'm not crazy about all the extra controls, the expense of the parts or the increase costs associated with the DEF purchase and milage drop.
But, I think it is a small price to pay for having a tailpipe that is still as clean (bright stainless) on the "inside" after almost 15K miles!

And I haven't had to clean "black stuff" (soot) off the side of the trailer since we started towing with the 2011.
 

Crumgater

Well-known member
I read a lot about regen/filter cleaning recently... here and at the Ford Truck forum. We are not alone, in that we see the 'regen' message more often when towing - not less. Seems very counterintuitive. Especially since the EGR temp got so high that at one point during our 2,000 mile trip the truck went into 'limp' mode - which scared the #$%! out of this diesel newbie. A nice coast down hill to a rest stop where we sat for 15 minutes trying to decide what to do next gave the truck systems time to reset... and we had no more problems during the remaining 3 hours of our week-long adventure.

As for additives, we have the 2008 F350 6.4l version. Purchased used in 2011 from a Ford dealer. They never mentioned anything about additives, so we've never used any. But, I plan on asking them in the near future. We see our mileage drop considerably with the winter fuel mix around here (Seattle metro area), and we stick with Chevron's diesel when we can. I'm wondering if an additive might help that as well - after reading this thread, doesn't sound like that's a likely outcome.
 

ricatic

Well-known member
I read a lot about regen/filter cleaning recently... here and at the Ford Truck forum. We are not alone, in that we see the 'regen' message more often when towing - not less. Seems very counterintuitive. Especially since the EGR temp got so high that at one point during our 2,000 mile trip the truck went into 'limp' mode - which scared the #$%! out of this diesel newbie. A nice coast down hill to a rest stop where we sat for 15 minutes trying to decide what to do next gave the truck systems time to reset... and we had no more problems during the remaining 3 hours of our week-long adventure.

As for additives, we have the 2008 F350 6.4l version. Purchased used in 2011 from a Ford dealer. They never mentioned anything about additives, so we've never used any. But, I plan on asking them in the near future. We see our mileage drop considerably with the winter fuel mix around here (Seattle metro area), and we stick with Chevron's diesel when we can. I'm wondering if an additive might help that as well - after reading this thread, doesn't sound like that's a likely outcome.

Your 2008 6.4 Navistar powered truck is quite different than the new 6.7 powered truck. You do not have DEF injection. Your truck is equipped with a Siemens fuel injection system. These trucks have also proved to have a delicate HPFP. I would highly recommend using the PM22A additive in your truck.

Your regeneration mode is significantly different than the 6.7. Where the 6.7 only uses one bank of cylinders for regeneration fuel injection, your 6.4 engoine uses both cylinder banks. The 6.4 has been reported to "make oil" during regeneration. This means that a small quantity of diesel fuel injected for regeneration purposes ends up in the crankcase. This phenomena has not appeared in the 6.7.

Most 6.4 owners are quite happy with their trucks. Keep up on the maintenance and be careful with your fuel quality...and enjoy that truck...

Regards
 

ncc1701e

Well-known member
With the first 1500 miles on the engine, I've noticed the regen process three times. After reading and rereading the owners manual, the only thing I'm clear on is the truck is suppose to do this automatically and unless you're looking at the screen when the process initiates you'll never know that is happening. According to the manual, sometime between every 500 and 1000 miles the system will do its thing. This truck just has so many computer controlled and initiated items I feel like being in a sci-fi movie. Sure is a long ways from the good ole days of tracking every oil change vs mileage to keep things running smoothly. I'm still looking for some of the filters and water separators that need routine service, too darn much stuff under the hood (LOL). On the positive side, without the trailer the truck is getting 19.5mpg as measured and calculated (not just what the computer says). Now when we pick the trailer up next month for our winter pilgramige I'm sure that will change.

I just spent 3 days putting Air Lift air bags and on-board air compressor on the truck. The number of threads I've seen where it only takes 2 or 3 hours to put on the bags is higher than I count. I do not know what truck they were putting the bags on, but one thing for sure, it was not a F250 with all the emmission controls on them the 2011 and 2012 F250s have on them. This is the second F250 I put these bags on and both took me forever. Maybe, I'm just not as goo a mechanic as I thought (LOL). Sure is sweet with that on-board compressor though.
 

Wmnmy

Well-known member
With the first 1500 miles on the engine, I've noticed the regen process three times. After reading and rereading the owners manual, the only thing I'm clear on is the truck is suppose to do this automatically and unless you're looking at the screen when the process initiates you'll never know that is happening. According to the manual, sometime between every 500 and 1000 miles the system will do its thing. This truck just has so many computer controlled and initiated items I feel like being in a sci-fi movie. Sure is a long ways from the good ole days of tracking every oil change vs mileage to keep things running smoothly. I'm still looking for some of the filters and water separators that need routine service, too darn much stuff under the hood (LOL). On the positive side, without the trailer the truck is getting 19.5mpg as measured and calculated (not just what the computer says). Now when we pick the trailer up next month for our winter pilgramige I'm sure that will change.

I just spent 3 days putting Air Lift air bags and on-board air compressor on the truck. The number of threads I've seen where it only takes 2 or 3 hours to put on the bags is higher than I count. I do not know what truck they were putting the bags on, but one thing for sure, it was not a F250 with all the emmission controls on them the 2011 and 2012 F250s have on them. This is the second F250 I put these bags on and both took me forever. Maybe, I'm just not as goo a mechanic as I thought (LOL). Sure is sweet with that on-board compressor though.
The v10 I had prior to this power stroke diesel (2011) I put bags on myself took longer than the 2hrs hahah so this tim I had 4wheel auto in Vegas put the Firestone heavy duty air bags and on board compressed air kit took them a whole day and they are professionals worth every penny . Trying it out this week on a 800+ mile trip
 

lwmcguir

Well-known member
Definitely took longer on my 2005 back when I put them on it as well. Just moving the brake cable and rivet took quita a while. The on board compressor is the only way to really get the maximum benifit from them for sure.
 

Wmnmy

Well-known member
Definitely took longer on my 2005 back when I put them on it as well. Just moving the brake cable and rivet took quita a while. The on board compressor is the only way to really get the maximum benifit from them for sure.
I don't know how I did without it and I see how great it is having the on board compressor if u need air quite always from a gas station or truck stop it worked like a champ and with the bags our trip was terrific I did not get chucking and a very smooth ride wife enjoyed it and she felt the difference with this power stroke than the v10 we got rid of .
 

ncc1701e

Well-known member
Can I add another question to this thread? Being very new to diesel operations, I was just wondering about engine warmup and idleing. Seems that the guys with diesels always do a long idle warmup. Is there a piece of logic I should be aware of here guys. Remember this is my first diesel truck so I"m pretty dumb here.
 

JohnDar

Prolifically Gabby Member
Don't know about Fords (other than they seem to require a lot of add-ons to make them worthy of pulling a trailer :D), but with my 2009 GMC when the "glow plug" indicator shuts off, I fire it up and hit the road. No long idling required. I've had it 3 years and it's still running like new.
 

porthole

Retired
Can I add another question to this thread? Being very new to diesel operations, I was just wondering about engine warmup and idleing. Seems that the guys with diesels always do a long idle warmup. Is there a piece of logic I should be aware of here guys. Remember this is my first diesel truck

Modern passenger vehicle engines are designed to be easy to start and to warm up quickly, gas or diesel.
Because of the inherent design of a diesel, which includes large capacity cooling systems and heavy duty components, long idle times are both a waste of fuel and potentially detrimental to engine life.
Less then ideal operating temps and slow engine speeds (idle) can lead to something known as "wet stacking". This is excessive unburned fuel either in the exhaust system or washing down the cylinders walls in to the oil pan.

On my vehicles I start and let them run maybe 10-30 seconds, give the oil a chance to circulate in both the engine and transmission. Then I put it in gear and go.
GM's have another concern with excessive cold idle. The Allison in the GM flows fluid through the cooler lines as soon as the engine is running. Viscous cold fluid does not flow as well and the transmission cooler lines on the GM's are a weak point. The lines which are aluminun with sections of rubber hose, are prone to leak at the metal/rubber junction. There are 3 of these lines, pricey and a pain to change. And you can ask me how I know that :cool:

So, start your truck, give it a few seconds to get the blood flowing and put it drive.

Now if it is really cold, a block heater is certainly a big plus.
 

wdk450

Well-known member
Modern passenger vehicle engines are designed to be easy to start and to warm up quickly, gas or diesel.
Because of the inherent design of a diesel, which includes large capacity cooling systems and heavy duty components, long idle times are both a waste of fuel and potentially detrimental to engine life.
Less then ideal operating temps and slow engine speeds (idle) can lead to something known as "wet stacking". This is excessive unburned fuel either in the exhaust system or washing down the cylinders walls in to the oil pan.

On my vehicles I start and let them run maybe 10-30 seconds, give the oil a chance to circulate in both the engine and transmission. Then I put it in gear and go.
GM's have another concern with excessive cold idle. The Allison in the GM flows fluid through the cooler lines as soon as the engine is running. Viscous cold fluid does not flow as well and the transmission cooler lines on the GM's are a weak point. The lines which are aluminun with sections of rubber hose, are prone to leak at the metal/rubber junction. There are 3 of these lines, pricey and a pain to change. And you can ask me how I know that :cool:

So, start your truck, give it a few seconds to get the blood flowing and put it drive.

Now if it is really cold, a block heater is certainly a big plus.

Long diesel idles also tick off the other folks at the campgrounds, too!
 

porthole

Retired
Long diesel idles also tick off the other folks at the campgrounds, too!

You can't smell my new truck, even standing next to it and 15' away you can barely hear it.
Would not want one of the earlierFords or Cummins next to me early in the morning though.
 
Top