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3.0 Derating Problem SOLVED…(maybe)

Maximus Gladius

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Well, I don’t drive a diesel so why would this guy who owns a gasser have anything to say about this? I did have the 94 Dodge Cummins and loved it when I bought it new in 94/95 but this post isn’t even about the DEF system issues.

The 3.6 and 3.0 has something in common they both need to run and operate in peak performance and that’s OXYGEN.

What I haven’t seen, at all, in the many comments and complaints forum pages of “over heating” and “derating” for the 3.0 is someone saying “my derating problem or plugged up soot problem is caused by a lack of oxygen”. (Take a moment to think about this)

Most comments I read when derating and power limping takes place is when someone is driving their diesel UP some mountainous pass or UP some grade and the engine craps out and can only limp along or it just can’t go any more.

Now, my uneducated and simple brain has been critically thinking about your derating problems and:
1. No body talks about the elevation derating took place going up some grade or mountain pass.
2. No body has understood yet, the higher you go, the less oxygen there is and either the computer is cutting back the fuel to match the oxygen (power loss) OR it’s dumping in more fuel because your foot is pressing the peddle in more to keep the speed up where it was at lower elevation, and this just causes more heat and plugs up stuff.

If your driving around sea level, everything runs great, engine is happy, you’re getting great milage and you barely need to stomp on the throttle to maintain speed….now try that at 12,000 feet and tell me it’s the same experience.

Let’s go higher… think of being on a climbing expedition to mark off your bucket list. You picked some peak of the Himalayan mountains and you have to take along oxygen tanks to get your sorry ass to the top and it’s all you can do just to get your own weight up there. ….now shed the oxygen tank and pull up a couple climbers on a sled and see if you would also derate and blow a code.

So, consulting with goggle and Ai, the 3.0 engine is manufactured in Cento, Italy at the elevation of 49 (forty nine) ft. and I’m ASSUMING the engine is calibrated to it’s computer here (I may be wrong) but I think the manufacturer would want to make sure the engine is in proper running order before shipping to the Gladiator assembly complex in Toledo, Ohio, elevation at 604 ft.

So let’s now remember the good ‘ol days where back in the 80’s our engines had distributors and points and as we drove up higher grades and mountain passes our engines would start knocking so you would just pull over and turn the distributor to adjust the timing and off you go with no knocking. It was to compensate for the lack of oxygen at the higher elevation. So, now we don’t deal with distributors but the computer makes those timing adjustments the higher you go until it can’t and as you keep climbing the more your stepping into the throttle, more heat is generated and the less oxygen there is.

So here’s my fix (idea) for this (keep reading) let’s say the assembly plant in Ohio recalibrates the engine to 604 ft, from 49 feet before putting it on the transport truck to deliver them all over the place. When you’ve taken this truck on a road trip to New Mexico or AZ, NV or maybe even to Trinidad, Colorado where I’m told you can’t get a hot cup of coffee or hot shower there because the elevation is over 6000 ft, RECALIBRATE the computer when you’re starting to notice derating because as I said, the computer can only adjust so much before it can’t or it wasn’t programmed to adjust more than it’s designed to do. I think recalibrating would reset it at the elevation the truck is having problems with and you’d be good to go.

I have a well seasoned red seal friend that is invited all over the world to speak to heavy industry shop mechanics to explain or examine major engine issues on the big stuff like million dollar cat engines for fracking and other oil exploration companies and he told me of one call out to a drill site in New Mexico where all these fracking units were headed up some crazy high mountain pass until the semis pulling the fracking units couldn’t go up any further. They all derated and stopped on the highway. My friend was called and he took an emergency flight out to the site and he told me what was funny is that you could see from the highway the drill sites but the trucks couldn’t go any more. Elevation was around 9000 ft. He told all the drivers who were just sitting there to “back up the units in reverse to the site, the gearing in reverse is much higher and doesn’t require the HP going forward needs. So they all backed up to the drill site and set up. The next problem was the CAT engines could only perform at limited power and what was not understood by all the equipment operators and mechanics is that on every engine, CAT had a small aluminum spec plate that said MAX elevation for peak performance was just over 700 ft. ….and they’re having to do this job at 9000 ft.

(disclaimer) I’m speculating here, because I’m good at it.
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rharr

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The 3.0 is variable vane turbo motor. ELevation doesn't play a big roll, the turbo will build the pressure it needs by controlling the vanes and blow off.

Same reason they supercharged WW2 aircraft, to take the lack of air density out of the equation.
 

DylanM

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x2, definitely not a lack of oxygen problem as the turbo is quite capable of providing full boost at most any altitude you're able to drive. It's a heat issue.

Short and sweet, the 3.0L PCM is programmed to pull the available power back as coolant and oil temps rise above an initial set point, then chop it back considerably above a second point to prevent damage to the engine. Typically this is a legitimate situation where the engine is getting hot due to high load exacerbated by the size limitation of the cooling stack in the JT, but it can also be triggered by electrical anomalies.
 
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Maximus Gladius

Maximus Gladius

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The 3.0 is variable vane turbo motor. ELevation doesn't play a big roll, the turbo will build the pressure it needs by controlling the vanes and blow off.

Same reason they supercharged WW2 aircraft, to take the lack of air density out of the equation.
So where higher elevation is where I’m reading these derating issues are taking place, a bigger turbo is needed (like a supercharger) to send more, less dense air through the intake. Less dense means the oxygen is missing so if more “air” containing what little oxygen is mixed in would hopefully mean there’s enough oxygen tossed in to do the job.

Let’s say the vanes in the turbo are controlled as adjusted as they can to pull in as much air and pressure as it can, until more is needed but it’s not mechanically designed to do more, derating takes place unless you could just pull over and slap in a ‘plug and play’ bigger turbo on the side of the road and go. So it’s either the turbo is too small (but good enough at 49 ft elevation but not good enough at 9000 ft, …spanking this engine at 9000 ft won’t give you the same performance if spanked at sea level. It won’t happen unless 9000 ft has the same oxygen density as sea level.
 
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Maximus Gladius

Maximus Gladius

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x2, definitely not a lack of oxygen problem as the turbo is quite capable of providing full boost at most any altitude you're able to drive. It's a heat issue.
Would you say that these 3.0’s are having the same “heat issues” at sea level as those I’m reading occurring at higher elevations. We could say sea level and higher elevations is “apples to apples” comparison?

If I was to run a marathon at 9000 ft and do the same at sea level, I know I’d perform better where oxygenated air is more dense.

If I was a betting man and my 3.0 was derating and losing power at higher elevations, if I could snap my fingers and instead of being at 9k or 10k elevation, all of a sudden be at sea level, the temps would come back to normal, power would come back and derating would stop unless of course it’s an electrical issue
 

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Rusty PW

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Max boost pressure is around 30 psi. Regardless of elevation. It's pulling in the same amount of air at sea level as 9,000 ft. To get more air in. You need a larger turbo plus tuning. Which generates more heat. Requiring larger radiator.
 

Ericshere03

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Would you say that these 3.0’s are having the same “heat issues” at sea level as those I’m reading occurring at higher elevations. We could say sea level and higher elevations is “apples to apples” comparison?

If I was to run a marathon at 9000 ft and do the same at sea level, I know I’d perform better where oxygenated air is more dense.

If I was a betting man and my 3.0 was derating and losing power at higher elevations, if I could snap my fingers and instead of being at 9k or 10k elevation, all of a sudden be at sea level, the temps would come back to normal, power would come back and derating would stop unless of course it’s an electrical issue
I have started seeing temps rise just off the desert floor, perhaps 1500ft elevation, 2,000 tops. The temperature was about 100 degrees and dry. This was the beginning of my ascent to 8000ft and 70-80 degree weather. Oddly, on my way back home, I was still around 7000ft elevation and ascending a small hill and saw the temps rise, it was about 80-85 degrees at this point.

bottom line, the cooling system is insufficient…

For the record, I’ve seen temps hit 244/264 degrees (water/oil) . I tow about 55mph and will speed up to 65mph if it’s flat and low traffic. When I start ascending a hill, I pick up a little speed and downshift , allowing speed to some down a little bit as I am ascending, then I’ll slowly accelerate of the descent of each hill.

on flat terrain, I never see the coolant creep much past normal
 

Ericshere03

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I have started seeing temps rise just off the desert floor, perhaps 1500ft elevation, 2,000 tops. The temperature was about 100 degrees and dry. This was the beginning of my ascent to 8000ft and 70-80 degree weather. Oddly, on my way back home, I was still around 7000ft elevation and ascending a small hill and saw the temps rise, it was about 80-85 degrees at this point.

bottom line, the cooling system is insufficient…

For the record, I’ve seen temps hit 244/264 degrees (water/oil) . I tow about 55mph and will speed up to 65mph if it’s flat and low traffic. When I start ascending a hill, I pick up a little speed and downshift , allowing speed to some down a little bit as I am ascending, then I’ll slowly accelerate of the descent of each hill.

on flat terrain, I never see the coolant creep much past normal
I guess my point here is that elevation may not play much a difference
 

DylanM

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Would you say that these 3.0’s are having the same “heat issues” at sea level as those I’m reading occurring at higher elevations. We could say sea level and higher elevations is “apples to apples” comparison?

If I was to run a marathon at 9000 ft and do the same at sea level, I know I’d perform better where oxygenated air is more dense.

If I was a betting man and my 3.0 was derating and losing power at higher elevations, if I could snap my fingers and instead of being at 9k or 10k elevation, all of a sudden be at sea level, the temps would come back to normal, power would come back and derating would stop unless of course it’s an electrical issue
Yes, the heat issue can happen anywhere from below sea level in Death Valley all the way up to high mountain passes in the Rockies, anywhere that you can put enough load on the engine long enough to get the coolant and/or oil temps high enough to cause the PCM to derate the engine's output.

To use your own analogy, imagine running atop Pike's Peak while wearing a breathing apparatus that allowed you to get the same amount of air and oxygen at 14,000 feet as you would at sea level -- that is what the turbo does for the 3.0L engine. Changes to altitude and air density don't matter because the turbo ensures that the same amount of air gets stuffed into the engine regardless.
 

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DylanM

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So where higher elevation is where I’m reading these derating issues are taking place, a bigger turbo is needed (like a supercharger) to send more, less dense air through the intake. Less dense means the oxygen is missing so if more “air” containing what little oxygen is mixed in would hopefully mean there’s enough oxygen tossed in to do the job.

Let’s say the vanes in the turbo are controlled as adjusted as they can to pull in as much air and pressure as it can, until more is needed but it’s not mechanically designed to do more, derating takes place unless you could just pull over and slap in a ‘plug and play’ bigger turbo on the side of the road and go. So it’s either the turbo is too small (but good enough at 49 ft elevation but not good enough at 9000 ft, …spanking this engine at 9000 ft won’t give you the same performance if spanked at sea level. It won’t happen unless 9000 ft has the same oxygen density as sea level.
Again, the stock turbo is capable of providing the same amount of boost atop a high mountain pass in the Rockies as it can at sea level. Thinner air may make the turbo work harder, but it still can get the job done to ensure the same horsepower and torque you have at sea level is still there when up at higher elevation. Yes you read that right, power on the 3.0 doesn't drop off as you gain altitude like it does with a naturally aspirated engine.

The only aspect of gaining elevation that can have an effect on the derating issue has nothing to do with oxygen content, and that is the capacity to shed heat to the ambient air decreases as its density goes down. Less dense air means less molecules available to absorb heat from the radiator (and thus from the coolant, oil, engine, etc) as they pass through. Of course on the flip side, less dense air also results in aerodynamic drag going down which means it requires less power to move the vehicle along... to a point.

To restate from earlier, it's a heat issue that causes derating, or more specifically, it's insufficient heat shedding capacity of the cooling system that leads to high temps that cause the PCM to reduce power in order to reduce heat production. Power equals heat, so reducing the amount of power the engine puts out reduces the heat that it creates.
 

nanook12

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As a pilot flying turbo charged twin - recips, the turbo would hold the boost way above any altitudes you are driving at in the USA. The slowing of the cooling air through the radiators, as you climb is the culprit. Keep the area in front of the grill clear…
 

Vtur

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Would you say that these 3.0’s are having the same “heat issues” at sea level as those I’m reading occurring at higher elevations. We could say sea level and higher elevations is “apples to apples” comparison?

If I was to run a marathon at 9000 ft and do the same at sea level, I know I’d perform better where oxygenated air is more dense.

If I was a betting man and my 3.0 was derating and losing power at higher elevations, if I could snap my fingers and instead of being at 9k or 10k elevation, all of a sudden be at sea level, the temps would come back to normal, power would come back and derating would stop unless of course it’s an electrical issue
Unfortunately, there's no high elevation hills at sea level 😂
 

Vtur

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Again, the stock turbo is capable of providing the same amount of boost atop a high mountain pass in the Rockies as it can at sea level. Thinner air may make the turbo work harder, but it still can get the job done to ensure the same horsepower and torque you have at sea level is still there when up at higher elevation. Yes you read that right, power on the 3.0 doesn't drop off as you gain altitude like it does with a naturally aspirated engine.

The only aspect of gaining elevation that can have an effect on the derating issue has nothing to do with oxygen content, and that is the capacity to shed heat to the ambient air decreases as its density goes down. Less dense air means less molecules available to absorb heat from the radiator (and thus from the coolant, oil, engine, etc) as they pass through. Of course on the flip side, less dense air also results in aerodynamic drag going down which means it requires less power to move the vehicle along... to a point.

To restate from earlier, it's a heat issue that causes derating, or more specifically, it's insufficient heat shedding capacity of the cooling system that leads to high temps that cause the PCM to reduce power in order to reduce heat production. Power equals heat, so reducing the amount of power the engine puts out reduces the heat that it creates.
Couldn't explained any better than this. I don't tow, so i haven't experience any derating traveling through the west high elevation hills. Highest oil temp was 269* at around 100* ambient temp.
 

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The Gladiator won't derate if drivers slow down. More fuel - more heat. I first discovered this when going up long steep mountain passes in which driving conditions forced a lower speed due to hairpin turns and a lower posted speed limit. I noticed that I could climb several thousand feet, and the oil temps stayed relatively cool when averaging 20 - 25 mph.

The issue is a lack of air flow. I can pull a 7,000 lb travel trailer over any mountain pass in North America with our 2020 Ram EcoDiesel and never reach derate, that's because the Ram has more air flow. So, even though the Ram EcoDiesel is tuned for more power out of the factory, it still runs much cooler than the Jeep due to air flow.

The Jeep engineers discussed this when the Gladiator EcoDiesel's dismal tow rating was released in comparison to the Pentastar. How could the Pentastar have better towing numbers? Well, Jeep said it had nothing to do with power, it had everything to do with the narrow grille opening found on the Jeep.
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