Sponsored

Ecodiesel power derating as temps rise?

AEsco48

Well-Known Member
First Name
AndresE
Joined
Oct 12, 2020
Threads
60
Messages
349
Reaction score
173
Location
Denver, CO
Vehicle(s)
2021 Rubicon Diesel
Occupation
Mech Engineer/MBA/Entrepreneur
I can think of a few tests to run. There will be multiple aspects to take in mind that i have not considered or have not written to make sure its an apples to apples comparison.

-Check if air is flowing in the right direction using little streamers inside the hood. If they pop out of the vents air is flowing in the right direction.

- Are temps being reduced? Temp probes, measure/compare temp with vents open and closed. (No wind day, same direction on same road, engine temp stabilized, load/speed
(correct speed to there can be enough thermal transfer for prob to actually measure temp of air)/rpm constant, at night). General Probe inside hood, probe inside by vent where air should be flowing, probe directly outside vent in area where air should be flowing, probe out side of hood off to the side.


Or you could strap someone to the hood and have them feel if warm air is coming out....
Sponsored

 
OP
OP
CrazyCooter

CrazyCooter

Well-Known Member
First Name
Tony
Joined
Nov 1, 2020
Threads
10
Messages
1,892
Reaction score
1,959
Location
Far NorCal
Website
www.overlandvehicledynamics.com
Vehicle(s)
1991 JEEP YJ, 2021 JTR Ecodiesel
Occupation
Specialty Off Road Shop Owner
I don't think the temp of the air coming out the vents is as important as more possible air velocity being drawn through the coolers in the grill?
 

AEsco48

Well-Known Member
First Name
AndresE
Joined
Oct 12, 2020
Threads
60
Messages
349
Reaction score
173
Location
Denver, CO
Vehicle(s)
2021 Rubicon Diesel
Occupation
Mech Engineer/MBA/Entrepreneur
I don't think the temp of the air coming out the vents is as important as more possible air velocity being drawn through the coolers in the grill?
True. There is the possibility that the vents in the hood allow more air into the front grill and it comes out some other area/exit... Very hard to measure.
Air speed will be harder to measure than temp
 
OP
OP
CrazyCooter

CrazyCooter

Well-Known Member
First Name
Tony
Joined
Nov 1, 2020
Threads
10
Messages
1,892
Reaction score
1,959
Location
Far NorCal
Website
www.overlandvehicledynamics.com
Vehicle(s)
1991 JEEP YJ, 2021 JTR Ecodiesel
Occupation
Specialty Off Road Shop Owner
Someone like Banks does a ton of testing of things.....I have to wonder what it was like to develop the Derringer for the Eco JT while testing on the dyno? Heat had to be a huge factor? Couple of dyno pulls, then cool down for 15 mins.
 

Sponsored

AEsco48

Well-Known Member
First Name
AndresE
Joined
Oct 12, 2020
Threads
60
Messages
349
Reaction score
173
Location
Denver, CO
Vehicle(s)
2021 Rubicon Diesel
Occupation
Mech Engineer/MBA/Entrepreneur
Someone like Banks does a ton of testing of things.....I have to wonder what it was like to develop the Derringer for the Eco JT while testing on the dyno? Heat had to be a huge factor? Couple of dyno pulls, then cool down for 15 mins.
Dont know anything about Banks other than having just gone to their website now and spent 3 min. But generally speaking even if the engine is tuned and has 60 more HP... the extra heat generated is generated for a short time while the extra power is being used. Its not like you are going to the race track and staying full power for 3 minutes per lap over and over. So probably adding 60hp is not so significant in the real world on a Jeep... Dont have any dyno experience and I have always kept my track cars stock in terms of the engine
 

Odubi

Well-Known Member
First Name
Shane
Joined
Sep 5, 2020
Threads
26
Messages
73
Reaction score
72
Location
Alberta Canada
Vehicle(s)
2021 Gladiator Rubicon Diesel
Occupation
Regional Service Manager
Dont know anything about Banks other than having just gone to their website now and spent 3 min. But generally speaking even if the engine is tuned and has 60 more HP... the extra heat generated is generated for a short time while the extra power is being used. Its not like you are going to the race track and staying full power for 3 minutes per lap over and over. So probably adding 60hp is not so significant in the real world on a Jeep... Dont have any dyno experience and I have always kept my track cars stock in terms of the engine
My biggest issue is everyone reply, the engineers have big $ to confirms everything is the best it can get but a few things always jump out at me.
1. heat isn’t the only factor they are trying to maximize
2. all their tests are on a stock Gladiator
We all for the most part mod the hell out of our Jeep’s so we change testing parameters with every mod. So with that people who design mods may improve on something that the engineers where never concerned with.
 
OP
OP
CrazyCooter

CrazyCooter

Well-Known Member
First Name
Tony
Joined
Nov 1, 2020
Threads
10
Messages
1,892
Reaction score
1,959
Location
Far NorCal
Website
www.overlandvehicledynamics.com
Vehicle(s)
1991 JEEP YJ, 2021 JTR Ecodiesel
Occupation
Specialty Off Road Shop Owner
There are many threads going right now about the heat issue that have more posts/followers, but I wanted to update my thread with today's test.......

Ambient temp in the valley (470')starting this test was 107° while the temp at the top (3450') of the test was 97°. Cab was already cooled off and A/C running on recirculate. (SAE J2807 test specifies the tougher to cool fresh air setting)

My JT has 2" springs in the front, 3/4" spacer rear, Airlift bags, 37's, soft tonneau cover, OEM steel bumper, Warn Zeon 10S, and Mopar low profile winch hoop.

Distance was 17 miles one way with 34 total miles traveled in the hills with 2980' elevation gained (470-3450'). The first 10 miles is twisting rolling hills with steady elevation gain while the last 7 miles includes some pretty serious gains including a 3 mile long 9% grade where I ended the test. Speed limit on this section of road is 55mph (CA towing speed limit anyway)

I was towing my PJ 5x10 single axle dump trailer with 13.35ft² frontal area. Trailer weight was approx. 5200lb loaded with tarped roadbase and GCVW was 11870lb. (70lb over the max rated GCVW....I ate too much for breakfast and a pair of motorcycle tires in the bed)

Overall she handled it like a champ on the flats and rolling hills with plenty of power to spare. I let faster traffic pass at every opportunity as I knew what was going to happen as the climb got steeper........ average 50mph, but before I made it to the 9% section, she was already derating and speed was dropping.....I let 3 Chevys with large RV's who had already caught up entering the highway from a side road pass as I drove on the shoulder. Right before the 9% I was down to 35mph, on the shoulder, and flashers on right as the water temp message popped up.....finally down 10 mph 1st gear rolling to let her cool off. Once the water temp dropped after a couple mins, I was able to climb the 9% in the slow lane safely at 25mph flashers on.....I reached the top where is was 97°.

Peak water temp was 248° and oil temp 264°. I am however thankful that the designers put safeguards in to save the drivetrain from the limitations of the cooling system, otherwise the Ecodiesel would never know this is the chokepoint and melt itself down! I bet it would do this test without breaking a sweat with a radiator on the roof?

Trip down was uneventful mostly in 4th gear with a few brake applications which I was impressed with. I thought for sure I was going to really miss my recently sold vehicles on the decent.....Dodge w/ Pacbrake and Jake in the Peterbilt 385, but she held back pretty well. It took 7 miles coasting down hill for the temps to drop/stabilize to water 206° and oil 217°. I never saw the trans temp above 217° during the test, which is nice!

Fuel economy was 17.6 indicated MPG for the 52 mile round trip from home which is pretty impressive to me considering the overall weight and elevation gain.

I will repeat this test with the stock tires and see is there is a significant difference, but I'm not expecting much. The 8 speed has gears so close together that I don't think there is much lost in the overall gearing.

I think I have pretty much confirmed this truck isn't going to work for my intended purpose (or as advertised) which was to travel to far away off road trails, camp, and tow a small RV under 4000lb possibly with a dirt bike in the bed. It has already overheated with much lighter loads and cooler temps........
 
Last edited:

Gmac03

Well-Known Member
Joined
Oct 19, 2020
Threads
2
Messages
129
Reaction score
148
Location
Syracuse, NY
Vehicle(s)
21 Willys D
Turbos are hot! Hard piping for the charge side pipes, wrapped or coated, turbo blanket to keep the heat on the turbine and not everything else, maybe look at a better higher flowing inter cooler, more rows, end tanks etc.

I’m very happy with mine and have no intention of ripping it apart and fabbing parts up, but all of that can be done for fairly cheap. It would be nice to see some aftermarket support on the turbo side though. 🤷‍♂️

And for those that want an oil cooler, throw a relocation kit on there and run it where ever you’d like. Might not be room sandwiched between the IC/Rad/AC but throw it about anywhere else.
 
OP
OP
CrazyCooter

CrazyCooter

Well-Known Member
First Name
Tony
Joined
Nov 1, 2020
Threads
10
Messages
1,892
Reaction score
1,959
Location
Far NorCal
Website
www.overlandvehicledynamics.com
Vehicle(s)
1991 JEEP YJ, 2021 JTR Ecodiesel
Occupation
Specialty Off Road Shop Owner
Turbos are hot! Hard piping for the charge side pipes, wrapped or coated, turbo blanket to keep the heat on the turbine and not everything else, maybe look at a better higher flowing inter cooler, more rows, end tanks etc.

I’m very happy with mine and have no intention of ripping it apart and fabbing parts up, but all of that can be done for fairly cheap. It would be nice to see some aftermarket support on the turbo side though. 🤷‍♂️

And for those that want an oil cooler, throw a relocation kit on there and run it where ever you’d like. Might not be room sandwiched between the IC/Rad/AC but throw it about anywhere else.
I'm not doing anything to the powertrain yet.......This is a new truck with 7.5 more years remaining on warranty?

I'll swap out to the stock tires and maybe pull the bar on the bumper and see if it makes any difference before complaining to Jeep. The other mods I've done will have no bearing on the heat issue.

I sold all of my heavily modded vehicles in favor of downsizing to simplify my life. I work on client vehicles 45+ hours a week and have no intentions of turning this truck into another project. I tried to buy it capable out of the box to avoid these issues! I dont even want to open the axle to change gears risking warranty issues.

Ill redo the test again tomorrow with the stock tires, no bar, and when valley temps are only 100° so we have a more comparable test to the J2807 test. I'm feeling like Jeep needs to come up with a cooling solution for us or buy them back. I bet i don't make it to the bottom of the 9% before she derates?
 
Last edited:

Sponsored

tjZ06

Active Member
First Name
TJ
Joined
Jul 7, 2021
Threads
1
Messages
31
Reaction score
47
Location
Palo Alto, CA
Vehicle(s)
'03 JGC Overland 4.7 HO, '18 JGC Trackhawk 6.2 SC
Occupation
Tech
There are many threads going right now about the heat issue that have more posts/followers, but I wanted to update my thread with today's test.......

Ambient temp in the valley (470')starting this test was 107° while the temp at the top (3450') of the test was 97°. Cab was already cooled off and A/C running on recirculate. (SAE J2807 test specifies the tougher to cool fresh air setting)

My JT has 2" springs in the front, 3/4" spacer rear, Airlift bags, 37's, soft tonneau cover, OEM steel bumper, Warn Zeon 10S, and Mopar low profile winch hoop.

Distance was 17 miles one way with 34 total miles traveled in the hills with 2980' elevation gained (470-3450'). The first 10 miles is twisting rolling hills with steady elevation gain while the last 7 miles includes some pretty serious gains including a 3 mile long 9% grade where I ended the test. Speed limit on this section of road is 55mph (CA towing speed limit anyway)

I was towing my PJ 5x10 single axle dump trailer with 13.35ft² frontal area. Trailer weight was approx. 5200lb loaded with tarped roadbase and GCVW was 11870lb. (70lb over the max rated GCVW....I ate too much for breakfast and a pair of motorcycle tires in the bed)

Overall she handled it like a champ on the flats and rolling hills with plenty of power to spare. I let faster traffic pass at every opportunity as I knew what was going to happen as the climb got steeper........ average 50mph, but before I made it to the 9% section, she was already derating and speed was dropping.....I let 3 Chevys with large RV's who had already caught up entering the highway from a side road pass as I drove on the shoulder. Right before the 9% I was down to 35mph, on the shoulder, and flashers on right as the water temp message popped up.....finally down 10 mph 1st gear rolling to let her cool off. Once the water temp dropped after a couple mins, I was able to climb the 9% in the slow lane safely at 25mph flashers on.....I reached the top where is was 97°.

Peak water temp was 248° and oil temp 264°. I am however thankful that the designers put safeguards in to save the drivetrain from the limitations of the cooling system, otherwise the Ecodiesel would never know this is the chokepoint and melt itself down! I bet it would do this test without breaking a sweat with a radiator on the roof?

Trip down was uneventful mostly in 4th gear with a few brake applications which I was impressed with. I thought for sure I was going to really miss my recently sold vehicles on the decent.....Dodge w/ Pacbrake and Jake in the Peterbilt 385, but she held back pretty well. It took 7 miles coasting down hill for the temps to drop/stabilize to water 206° and oil 217°. I never saw the trans temp above 217° during the test, which is nice!

Fuel economy was 17.6 indicated MPG for the 52 mile round trip from home which is pretty impressive to me considering the overall weight and elevation gain.

I will repeat this test with the stock tires and see is there is a significant difference, but I'm not expecting much. The 8 speed has gears so close together that I don't think there is much lost in the overall gearing.

I think I have pretty much confirmed this truck isn't going to work for my intended purpose (or as advertised) which was to travel to far away off road trails, camp, and tow a small RV under 4000lb possibly with a dirt bike in the bed. It has already overheated with much lighter loads and cooler temps........
Extremely useful, real-world data. Thanks for that! I'm in the Bay Area, well, kinda split between Bay and Vegas but the Gladiator, were I to get one would be for the Bay and towing my 2800lbs off-road trailer. Lots of places I go are up your way, so I'd regularly be hitting those same grades you tested on. Yes, 2800lbs is less than you had, but not enough less that I'm confident the cooling system could keep up. The entire reason I was considering a diesel Gladiator was because I fight heat issues with my 4.7HO WJ when towing the trailer, but I only see 230 tops in that. Unfortunately, the more I read here, the less I think a DJTR is right for me.

-TJ
 
OP
OP
CrazyCooter

CrazyCooter

Well-Known Member
First Name
Tony
Joined
Nov 1, 2020
Threads
10
Messages
1,892
Reaction score
1,959
Location
Far NorCal
Website
www.overlandvehicledynamics.com
Vehicle(s)
1991 JEEP YJ, 2021 JTR Ecodiesel
Occupation
Specialty Off Road Shop Owner
Extremely useful, real-world data. Thanks for that! I'm in the Bay Area, well, kinda split between Bay and Vegas but the Gladiator, were I to get one would be for the Bay and towing my 2800lbs off-road trailer. Lots of places I go are up your way, so I'd regularly be hitting those same grades you tested on. Yes, 2800lbs is less than you had, but not enough less that I'm confident the cooling system could keep up. The entire reason I was considering a diesel Gladiator was because I fight heat issues with my 4.7HO WJ when towing the trailer, but I only see 230 tops in that. Unfortunately, the more I read here, the less I think a DJTR is right for me.

-TJ
Did you read earlier on the thread where I derated and borderline overheated with temps in the 80s and only 2000lbs? 2800lb will be a problem for sure unless you only travel when it's cold. This issue did not surface on my Death Valley trip this winter, but it was way cooler and I was traveling with gas powered JKs that were slow up the hills........
 

tjZ06

Active Member
First Name
TJ
Joined
Jul 7, 2021
Threads
1
Messages
31
Reaction score
47
Location
Palo Alto, CA
Vehicle(s)
'03 JGC Overland 4.7 HO, '18 JGC Trackhawk 6.2 SC
Occupation
Tech
Did you read earlier on the thread where I derated and borderline overheated with temps in the 80s and only 2000lbs? 2800lb will be a problem for sure unless you only travel when it's cold. This issue did not surface on my Death Valley trip this winter, but it was way cooler and I was traveling with gas powered JKs that were slow up the hills........
I admit, I did not read the whole thread. But that seems to seal the coffin on my Diesel JT Rubicon dreams. Thanks again for the honest feedback and data.

-TJ
 
OP
OP
CrazyCooter

CrazyCooter

Well-Known Member
First Name
Tony
Joined
Nov 1, 2020
Threads
10
Messages
1,892
Reaction score
1,959
Location
Far NorCal
Website
www.overlandvehicledynamics.com
Vehicle(s)
1991 JEEP YJ, 2021 JTR Ecodiesel
Occupation
Specialty Off Road Shop Owner
I admit, I did not read the whole thread. But that seems to seal the coffin on my Diesel JT Rubicon dreams. Thanks again for the honest feedback and data.

-TJ
I hate to steer you away from this truck because I love it in every other way!

Stay tuned for the results of my test tomorrow morning. I just dont think the 37s are the cause, but I have to rule it out for the other naysayers and before I bring Jeep in on this complaint.
 

ShadowsPapa

Well-Known Member
First Name
Bill
Joined
Oct 12, 2019
Threads
178
Messages
29,084
Reaction score
34,569
Location
Runnells, Iowa
Vehicle(s)
'22 JTO, '23 JLU, '82 SX4, '73 P. Cardin Javelin
Occupation
Retired auto mechanic, frmr gov't ntwrk security admin
Vehicle Showcase
3
The choke point is the front grille area. The engineers have said, in interviews, that they have done all they can without changing the front end design. They use electric fans as there isn't room for an engine driven fan.
That's been the same conclusion of every article I've read on it, ever one.
Electric is more efficie
I agree with you here just from my experience in the automotive trade.

I did see a video over weekend where the guy did some testing in a wind tunnel with a smoke wand removing his hood and thought of these threads where people want to add venting. You could clearly see the vacuum into the radiator with the hood on, but hood removed it seemed to want to divert air over the grill rather than through. for $495hr, one could maybe see where FCA screwed this up? :CWL:

Have a look for yourself!
Funny thing - I found a couple of other similar tests, too. One with a sports car..........same effect.
If you look as the shape and placement of the shields and baffles in there, makes some sense.
But I'm not a member of SAE.
Sponsored

 
 



Top