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Discussion Starter #101
@wjhaze you may have something else going on. I have towed a large farm tractor on a tandem axle trailer (About 7000lbs total) numerous times since getting the HDDS tune, and I’ve never seen oil temps higher than 220, even on 90° days.
 

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All tunes that disable the egr and optimize combustion well run hotter when working them hard. The reason for this is in cylinder temps are hotter than stock. The egr purpose in life is the keep in cylinder temps down around 2500 F to minimize the production of Nox emissions. Even at 260 F oil temps your not at the derate temp yet and even if you hit derate temps it well just reduce power to protect itself.
Pretty sad for a truck to get that hot going 45 mph Towing less than half of its rated towing capacity. This is my 3rd Ecodiesel and none of them ever got that hot with the GDE tune.
 

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@wjhaze you may have something else going on. I have towed a large farm tractor on a tandem axle trailer (About 7000lbs total) numerous times since getting the HDDS tune, and I’ve never seen oil temps higher than 220, even on 90° days.
That’s interesting. I run that hot empty but with the stock tune I was running around 208.
 

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Discussion Starter #104
That’s interesting. I run that hot empty but with the stock tune I was running around 208.
Not towing, with tune, I have never seen over 210 for oil, even on the 90° days. 2015 Tradesman. I think I remember seeing that the newer trucks run hotter stock...maybe with a tune as well?
 

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Not towing, with tune, I have never seen over 210 for oil, even on the 90° days. 2015 Tradesman. I think I remember seeing that the newer trucks run hotter stock...maybe with a tune as well?
Thats strange, imo. I have a great high flowing grill, and my truck (2014) will hit 208-220 degrees stock or tuned. I have a 5% incline near my house I go up daily and my oil will hit 220 almost every time I go up that.

Considering the 2 stage thermostat in our trucks doesn't fully open until 230 degrees, I would find it near impossible to not occasionally hit the 220s.

To the OP, As far as the tune goes, I'm assuming its a GDE tune, or at least extremely similar (and endorsed by GDE themselves). My GDE tune will up my oil temps about 8-10 degrees. I've ran this same 5% grade hill, which is exactly 3 miles, with the same trailer back to back with 3 tunes and GDE is consistently 8-10 degrees hotter by the time I hit the top of the hill. This is due to the fact they they have a hotter combustion cycle to improve efficient. They also reduce the amount of fuel injected with a lot of pilot, post and pre injections, giving an overall leaner burn, which also makes the engine a bit louder, a bot more diesel clatter, which I personally like. The factory tune is a very dirty tune and produces a lot of soot. But, more fuel allows temps to stay lower, as well as the EGR. The combination of the pilot injections, EGR and a richer overall tune keeps the temps down.


When I tow, I use one of my other tunes to help keep temps down. One of the tunes actually kicks the cooling fan on a few degrees lower (at 224 degrees, stock is 228-230 I believe). When I want the best fuel economy for commuting and everything else, I use GDE.
 
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Discussion Starter #106 (Edited)
Thats strange, imo. I have a great high flowing grill, and my truck (2014) will hit 208-220 degrees stock or tuned. I have a 5% incline near my house I go up daily and my oil will hit 220 almost every time I go up that.

Considering the 2 stage thermostat in our trucks doesn't fully open until 230 degrees, I would find it near impossible to not occasionally hit the 220s.

To the OP, As far as the tune goes, I'm assuming its a GDE tune, or at least extremely similar (and endorsed by GDE themselves). My GDE tune will up my oil temps about 8-10 degrees. I've ran this same 5% grade hill, which is exactly 3 miles, with the same trailer back to back with 3 tunes and GDE is consistently 8-10 degrees hotter by the time I hit the top of the hill. This is due to the fact they they have a hotter combustion cycle to improve efficient. They also reduce the amount of fuel injected with a lot of pilot, post and pre injections, giving an overall leaner burn, which also makes the engine a bit louder, a bot more diesel clatter, which I personally like. The factory tune is a very dirty tune and produces a lot of soot. But, more fuel allows temps to stay lower, as well as the EGR. The combination of the pilot injections, EGR and a richer overall tune keeps the temps down.


When I tow, I use one of my other tunes to help keep temps down. One of the tunes actually kicks the cooling fan on a few degrees lower (at 224 degrees, stock is 228-230 I believe). When I want the best fuel economy for commuting and everything else, I use GDE.
So I towed the tractor w/trailer, 42 miles one way today, and I paid close attention to my temps. The outside temp was 72°, and I was on hilly country roads, averaging about 50 mph. The hottest my oil got was 215 over one large hill. Most of the trip it was around 206-208. This is normal for my truck, and without towing the trailer I average around 202 for both oil and coolant (actually coolant is usually 2 degrees cooler). HDDS tune seemed to make no noticeable difference in my oil temps.
 

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The pilot injection being turned off helps tremendously with soot, and gives the truck the diesel sound.
You should be able to view a regen in progress in the dash menu, if the HD supply tune enables messages like the GDE tune did.
What is the theory that suggests the pilot injection causes soot ?? Pilot injection is to make the engine quieter mostly at idle like at stop lights it should actually do the opposite of create soot it should reduce it.
 

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What is the theory that suggests the pilot injection causes soot ?? Pilot injection is to make the engine quieter mostly at idle like at stop lights it should actually do the opposite of create soot it should reduce it.
Pilot injections = unburnt fuel = soot. It really is that simple. Please explain your theory of pilot injection reducing soot.
 

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Pilot injections = unburnt fuel = soot. It really is that simple. Please explain your theory of pilot injection reducing soot.
While more or less correct, its not that simple. The pilot injection triggers combustion to start earlier, which causes smoother combustion and less noise. But another result is lower cylinder pressure and thus lower temperatures. This results is less NOx but more soot. Also, the pilot injection aids in cold starts, but some power loss since detention is occurring ahead of the stroke.

Note that EGR has a similar effect. Lets funnel some of that left-over air/fuel mixture back into the intake, which results in the same behavior. Since the air is not "clean air" it lowers cylinder pressure and thus lower temperatures again. Yay, less NOx but more soot again. Now the EPA has dropped NOx to "acceptable" levels, but we have to do something about at that darn soot. Let's add a DOC (Diesel Oxidation Catalyst). Nope not good enough. Say hello to to the DPF. Cool, diesels aren't smokey anymore, but ya know, I think we need lower NOx levels. Thank goodness for DEF (Diesel Exhaust Fluid).

And now you have a modern diesel. Of course manufacturers have been more concerned about one-upping each others HP and TQ numbers, so rather than making all this added stuff work better or alternate means to meet emissions standards we have common issues with just about every piece of emissions equipment on the truck. Maybe post DPF EGR is a step in the right direction, but it looks like so far this is being used minimally in place of the "Hot" EGR.
 

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Pilot injection is so small it is insignificant it is used to reduce that diesel sound at idle a lot of people don't like. The FCA high pressure fuel system is so fast it can break the fuel injection on the power stroke up into several pulses and I suspect they do just that to reduce peak cylinder pressure reduce combustion temperature to reduce Nox at the expense of producing more soot.
 

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FYI, Pilot injection typically increases peak firing pressure on a diesel engine. The main purpose of single, double or triple pilot injections before the main is to slow the rate of cylinder pressure rise. This reduces NOx formation and engine radiated noise. Soot typically increases with pilots, but this is very contingent on the combustion bowl shape, injector spray angle and dwell time between pilot/main events.

Post injection is just as important as the pilots for soot control. Post is used during warm-up and on the emission cycle for speeding the catalyst light-off. The way FCA has it setup is sad as the post is also increasing soot formation.
 

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FYI, Pilot injection typically increases peak firing pressure on a diesel engine. The main purpose of single, double or triple pilot injections before the main is to slow the rate of cylinder pressure rise. This reduces NOx formation and engine radiated noise. Soot typically increases with pilots, but this is very contingent on the combustion bowl shape, injector spray angle and dwell time between pilot/main events.

Post injection is just as important as the pilots for soot control. Post is used during warm-up and on the emission cycle for speeding the catalyst light-off. The way FCA has it setup is sad as the post is also increasing soot formation.
Thanks for the information.
were these problems resolved or mitigated in the pre-EPA GDE hot tune I have installed?
 

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FYI, Pilot injection typically increases peak firing pressure on a diesel engine. The main purpose of single, double or triple pilot injections before the main is to slow the rate of cylinder pressure rise. This reduces NOx formation and engine radiated noise. Soot typically increases with pilots, but this is very contingent on the combustion bowl shape, injector spray angle and dwell time between pilot/main events.

Post injection is just as important as the pilots for soot control. Post is used during warm-up and on the emission cycle for speeding the catalyst light-off. The way FCA has it setup is sad as the post is also increasing soot formation.
I don't know exactly what FCA has done because I don't have the data. I agree with some of what you say but you are mixing and matching theory to suit your self. Originally pilot injection was used to control the noise diesel engines made at idle period by reducing the % of fuel ( aprox the first 5% of the main ) that results in uncontrolled combustion thus reducing noise.
 

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I don't know exactly what FCA has done because I don't have the data. I agree with some of what you say but you are mixing and matching theory to suit your self. Originally pilot injection was used to control the noise diesel engines made at idle period by reducing the % of fuel ( aprox the first 5% of the main ) that results in uncontrolled combustion thus reducing noise.
Mixing and matching theory to suit myself...what are you referring to? My background on diesel combustion is a bit more detailed than than the HPA class, that was more of an introductory lessen. If you really want to dive into combustion research you need a Kistler Kibox to measure cylinder pressure and combustion events in live time. I tried to get Chrysler to purchase one of these for emission development way back in 2004 when working with them on some projects. They never bought one due to cost, which was bs. The Kibox is the gold standard for anything combustion related. We have one of these in house and use it for all our development projects.

FYI, post injection is more critical for meeting EPA emission standards vs. pilot due to the thermal requirements in the exhaust system to conversion efficiency. If you cannot get proper light-off by the middle of the second hill on the FTP75 emission test, you have no chance of passing the federal requirements.
 

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Sounds good now if you could lower the cost of your tune so we can afford it that would be great, the cost in CDN dollars is some where around $2000.00 most cannot afford that. What connection do you have with HD diesel supply ? you mentioned they have a more refined tune than others.
 
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