Ecodiesel power derating as temps rise?

[22EcoDs]

If you note he ambient temps in these pics.....could you agree the cooling system is undersized? Nothing is in danger of exploding, but the temps are much higher than any other vehicle I've operated in the past 30 years. 30° ambient would think it could keep anything cool.

Forgive me if you already stated, but what was your situation in these pics? Lift, Tire size, Towing how much and how much in cabin? I see the 2kft difference and 18* temp difference.

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[CrazyCooter]

Those are high temps for the ambient air temp - but to say that it's all cooling system being undersized is suggesting that EVERYONE will have the same issue.
IS that the case? Does every ecodiesel JT owner have this same issue?
If some are towing at 90+ degrees on hills with no problem could suggest there's other things at play as well.....

By the same token, saying "it works fine" when the outside temp is only 70 also doesn't prove it's fine because it should also work like that at 90.

I think what we do out here on the west coast is much harder on things than what most are doing elsewhere in the country. Sure the highway system has 6% grades all over the country, but most of the ones leaving my city toward the mountains are 9% and our temps regularly go over 110° during the summer. Many of the smaller county roads heading up to where we go camping are more than 9%.

I think Jeep sized the cooling system just large enough to pass the J2807 towing test which it seems to do........Maybe that's all that could be done with what they were working with. I just don't think climbing 40mph on an interstate where the speed limit is 65-80mph is really all that safe.

The numbers I'm seeing thrown around here under similar conditions are right inline with mine.

 

[ShadowsPapa]

I think what we do out here on the west coast is much harder on things than what most are doing elsewhere in the country. Sure the highway system has 6% grades all over the country, but most of the ones leaving my city toward the mountains are 9% and our temps regularly go over 110° during the summer. Many of the smaller county roads heading up to where we go camping are more than 9%.

I think Jeep sized the cooling system just large enough to pass the J2807 towing test which it seems to do........Maybe that's all that could be done with what they were working with. I just don't think climbing 40mph on an interstate where the speed limit is 65-80mph is really all that safe.

The numbers I'm seeing thrown around here under similar conditions are right inline with mine.

Some have a posted minimum of something like 40 or 45, don't they?

 

[CrazyCooter]

Forgive me if you already stated, but what was your situation in these pics? Lift, Tire size, Towing how much and how much in cabin? I see the 2kft difference and 18* temp difference.

I was towing a 7x17 ultra light travel trailer weighing in right around 4K wet, 2 people in the cab, 150lb in the bed, with 37" tires 2"/.75" lift. I was traveling in central Utah in hilly country last week at the time of these pics during a 4300 mile SW National Parks tour. Every time we hit a good hill, my wife would grab the pbone to snap an pic as we crested the summit.

If you read this thread from the begining, you will see where I tow tested about 16 hours apart with the same trailer and road but with the stock tires. The results were pretty close to the same, but the ambient temp was a few degrees cooler.

 

[CrazyCooter]

Some have a posted minimum of something like 40 or 45, don't they?

Yes, the tow test requires 40mph for SRW trucks and 35mph for DRW. It seems my tuck just meets that requirement, so it "operates as designed"? Meets the minimum standard, but it's surley not the acceptable norm.

Here's a link to it: https://www.motortrend.com/how-to/1502-sae-j2807-tow-tests-the-standard/

 

[ShadowsPapa]

Yes, the tow test requires 40mph for SRW trucks and 35mph for DRW. It seems my tuck just meets that requirement, so it "operates as designed"? Meets the minimum standard, but it's surley not the acceptable norm.

Here's a link to it: https://www.motortrend.com/how-to/1502-sae-j2807-tow-tests-the-standard/

Not sure I posted my real meaning - was meaning to say 40 or 45 is the minimum speed posted on highways where the speed limit is 65 or over. I know there are signs around here - speed limit xxmph, minimum 40mph for example.
In other words, if you can't keep up 40, get the heck off the highway is what that sign says. And if you are going slower, you will be pulled over.

 

[CrazyCooter]

Not sure I posted my real meaning - was meaning to say 40 or 45 is the minimum speed posted on highways where the speed limit is 65 or over. I know there are signs around here - speed limit xxmph, minimum 40mph for example.
In other words, if you can't keep up 40, get the heck off the highway is what that sign says. And if you are going slower, you will be pulled over.

Here in CA, I have never seen minimum speed limit signs, but our traffic laws are pretty specific about impeding traffic.

 

[ShadowsPapa]

Here in CA, I have never seen minimum speed limit signs, but our traffic laws are pretty specific about impeding traffic.

Quote from our Iowa DOT -

The minimum speed limit on the interstate system in Iowa is forty miles per hour. A minimum speed may also be established on divided multilane highways if warranted by engineering and traffic investigations and established by Staff Action.

 

[steelponycowboy]

The air temp of only 70 makes a huge difference. The bigger the difference between the outside air and the coolant, the more heat that's removed more quickly. That's true for anything - grain drying equipment, hot water radiator in an older home, gas car, diesel truck, Trane heat pump, whatever.
That 20 degrees difference in air temp makes a world of difference in how much heat can be removed in any given time.

I realize that, but with temperatures we see here in AZ 8 months out of the year I'm thinking the diesel option was a bad choice on my part. When we were in the 100s earlier my oil was in the 250s on a short minimal grade. Then again ALL of my problems started when the DPF clogged up and shut me down. Before that I had no overheating issues and got 10 MPG better than I get today.

 

[steelponycowboy]

Used car prices are high as you know. Maybe time to unload it. No use being unhappy about a vehicle.

This is my 37th Jeep since 1972 and the only one that has had any issues. While prices are high why would I want to pawn off a vehicle with continued multiple issues on someone else. I'd much rather Jeep fit the damn thing to perform like it did before the regen issues at 8k miles

 

[ShadowsPapa]

I realize that, but with temperatures we see here in AZ 8 months out of the year I'm thinking the diesel option was a bad choice on my part. When we were in the 100s earlier my oil was in the 250s on a short minimal grade. Then again ALL of my problems started when the DPF clogged up and shut me down. Before that I had no overheating issues and got 10 MPG better than I get today.

Unreal that that diesel would be getting much worse mpg than my gasser gets.

I tried to educate myself more on what that particulate filter may have had to do with your current issues.
All I can think of is - something is plugged up down there.
Excessive backpressure causing heat - and poor mpg.

(what I was looking at for clues - but nothing stuck out)
https://www.uti.edu/blog/diesel/diesel-particulate-filters

 

[Rubiman]

My MPG sucks since the regen issue was fixed. I am lucky to average 15mpg when I was a solid 25-26 before. Going up a 4 mile, 6% grade my MPG is showing 4 mpg NOT towing. Dealers do not have a clue.

Same hill at 71 degrees outside I hit 268 on oil temps, at 61 degrees I hit 261, at 52 degrees last night, I still was at 254. The coolant temps also dropped accordingly. This motor or the programming has an issue for sure.

I'm thinking I should have got the gasser instead.

Why would the REGEN affect your MPG?

 

[ShadowsPapa]

Why would the REGEN affect your MPG?

Likely not the regen process itself, but the DPF may have sent things down the exhaust to plug things?
On the other hand, IF these have an active regen process like bigger trucks or bigger engines have, it uses fuel to regenerate -

Once the soot level reaches a certain point, the engine injects fuel into the exhaust stream, which goes over the oxidation catalyst and oxidizes the fuel to create heat. The heat created from the fuel oxidizing is then used to convert soot to carbon dioxide.

I don't know if THESE diesel DPF systems do that or not. Seems a bit overkill on these little trucks and engines.
Are these passive only, using HEAT, long trips, to regen or do they have an active process as well, and if so, what is it?

 

[Glad_he_ate]

We have active regen. Burns extra fuel to heat the dpf. I dont know if it's direct injection into the exhaust or just post combustion injection to send fuel down the exhaust to heat it. If your Intune with your truck you will notice when It happens. You will see a drop of a few mpg for 20 Min or so. One way to tell Is if you are coasting and watch the mpg meter you will notice that it will struggle to hit over 90 mpg while coasting. Keep an eye out and you will see it. And smell a different smell if you shut it off when it's doing its thing.
We also have passive regen while on the highway itll burn off if things get hot enough.

 

[steelponycowboy]

Why would the REGEN affect your MPG?

Because the DPF gets clogged because of regen issues

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