Diesel cooling options and ideas

[CrazyCooter]

I had a chance to do a little unloaded testing yesterday with our record breaking high of 119° in the valley. We did a 350 mile loop up to a high elevation of 6900' where air temps were just 82°.

I can say with absolute certainty that I have never seen coolant temps hovering so low at 200° + or -! Temps still climb at full throttle albeit slower, but recovery after getting off the throttle is quick.

When we returned home, the ambient temp was 118°, so I pulled out the thermal cam to record the delta in/out of the aux cooler with fan running on high and noted about 15°.

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[biodiesel]

@CrazyCooter, what is the hottest coolant and oil temps you've seen?

 

[CrazyCooter]

@CrazyCooter, what is the hottest coolant and oil temps you've seen?

3 years ago I could see 248/270 when towing at 100+ on the side of the road in limp mode. Never happened again after that last recall flash. I suspect they neutered it a little bit?

Peaks yesterday were 230/245 but I wasn't towing..... pedal did feel soft at times on the interstate @ 70mph closer we got to the valley where the high temps were happening.

 

[biodiesel]

3 years ago I could see 248/270 when towing at 100+.

Peaks yesterday were 230/245 but I wasn't towing..... pedal did feel soft at times on the interstate @ 70mph closer we got to the valley where the high temps were happening.

Air flow is very limited on the Jeep. My highest towing coolant temp on the Ram was 230*F and highest oil was 257*F. That's towing 7,000 lbs with cruise control, air condition on, and towing on a long steep grade at 65 MPH. I've towed throughout California, Neveda, Utah, Arizona, Colorado, and New Mexico. The highest ambient temperature that we've towed in was 117*F.

I've had the Gladiator hit 147* oil without towing!

 

[fourfa]

It’s derate season, sigh. It hit me Thursday driving up 108 around Sonora in the upper 90s air temp. Not towing, but loaded fairly heavy with Alu-Cab Canopy Camper, companion and our two big dogs, and all our gear and supplies. 37s on factory 3.73s FWIW. Oil temp only hit 245 or so when the derate happened. None of this is extreme conditions. Following closely what y’all are succeeding with.

 

[aFatBird]

I need to find a way to mount the bulletproof diesel kit since I don't have the frame horns anymore. Thinking about maybe making essentially a bull bar under my bumper to mount the rad to.

Wouldn't mind suggestions just saying.

 

[biodiesel]

Oil temp only hit 245 or so when the derate happened.

Do you mean coolant? Derate shouldn't happen when the oil reaches 245*F. Derate on the Ram is:
Coolant = 245* F
Oil = 270*F

 

[fourfa]

Nope, coolant was only 225 or so, and ~245 oil. Like I said, not extreme.

 

[pmpmstrb]

Here is my solution. It uses a Derale cooler mounted towards the rear under the bed. I am going to tap into the coolant just like BPD does, the return from the oil heat exchanger. I made a scoop for it that is easily removable. At a minimum I plan to run the scoop on long trips and definitely when towing. I am still waiting on my hose to show up so I can plumb it all in. I took the best pictures that I could. It's very difficult to do without the truck being on a lift.

 

[Primer Gray]

Here is my solution. It uses a Derale cooler mounted towards the rear under the bed. I am going to tap into the coolant just like BPD does, the return from the oil heat exchanger. I made a scoop for it that is easily removable. At a minimum I plan to run the scoop on long trips and definitely when towing. I am still waiting on my hose to show up so I can plumb it all in. I took the best pictures that I could. It's very difficult to do without the truck being on a lift.

You’ve got me wondering now about what kind of effect a run of that length is going have on flow…. that is a pretty lengthy detour for a hose that originally only spanned a couple inches..

I wonder, would it be possible to just tap into the main radiator and obtain the benefit of the larger hose size and thermostat controlled flow?

 

[ng1111]

It’s derate season, sigh. It hit me Thursday driving up 108 around Sonora in the upper 90s air temp. Not towing, but loaded fairly heavy with Alu-Cab Canopy Camper, companion and our two big dogs, and all our gear and supplies. 37s on factory 3.73s FWIW. Oil temp only hit 245 or so when the derate happened. None of this is extreme conditions. Following closely what y’all are succeeding with.

That's surprising that it derated at 245 oil temp. I was out this last week traveling across the country with temps from VA to Vancouver BC between 90 and 115 and my oil temps on my diesel Gladiator hit 255 and 260 all be it for short times and it did not derate. I was told Oil temps derate at 268 and coolant temps around 248 so I watch both. I do think the oil chosen by the dealership also has a lot to do with the higher temps on the oil. My oil change in CA was with Shell Rotella T6 which the dealer used and my oil temps from CA to VA stayed well below 245 the whole way and I have some high temps in OK, KY and VA and I was fully loaded in my AluCab. In VA the dealership did an oil change and I don't think they used a premium oil and saw my temps higher.

 

[biodiesel]

I was told Oil temps derate at 268 and coolant temps around 248 so I watch both.

The EcoDiesel goes into a soft derate at 268* and a hard derate at 270*F. If I remember correctly, Ram will display a warning message at 268* and then it will chime at 270*F. I'm not sure what the Jeep does.

My 2015 Ram EcoDiesel (Big Horn package) came factory with a restrictive grille. I hit derate twice, once in Colorado and once in New Mexico towing on a long steep grade. As soon as I replaced with the Tradesman grille (honeycomb design), it flowed something like 30% more air. I haven't had a derate since I swapped to the honeycomb grille.

Once the truck derates, there's definitely a serious lack of power, but at least I was able to get the travel trailer to the top where it would quickly cool on the descent. After many years of towing with the EcoDiesel, I realized that slowing down to very slow speeds makes a huge difference.

I don't plan to do much towing with the Gladiator, but the best advice I can offer is to slow down. That means if the posted speed limit is 70/75 mph, then you may need to slow down to 30 - 40 mph when towing on a long steep 6% grade. I say 6% because that is the maximum grade on the interstate. Once you're off the interstate, then you might encounter steeper and/or longer grades (6%, 7%, 8%, 9%). If a mountain road is really curvy, then the posted speed limit might be 35 mph. If that's the case, then you might be running 20 - 25 mph towing. The engine doesn't work near as hard at those speeds, thus keeping the oil and coolant temps in good shape.

 

[CrazyCooter]

The EcoDiesel goes into a soft derate at 268* and a hard derate at 270*F. If I remember correctly, Ram will display a warning message at 268* and then it will chime at 270*F. I'm not sure what the Jeep does.

My 2015 Ram EcoDiesel (Big Horn package) came factory with a restrictive grille. I hit derate twice, once in Colorado and once in New Mexico towing on a long steep grade. As soon as I replaced with the Tradesman grille (honeycomb design), it flowed something like 30% more air. I haven't had a derate since I swapped to the honeycomb grille.

Once the truck derates, there's definitely a serious lack of power, but at least I was able to get the travel trailer to the top where it would quickly cool on the descent. After many years of towing with the EcoDiesel, I realized that slowing down to very slow speeds makes a huge difference.

I don't plan to do much towing with the Gladiator, but the best advice I can offer is to slow down. That means if the posted speed limit is 70/75 mph, then you may need to slow down to 30 - 40 mph when towing on a long steep 6% grade. I say 6% because that is the maximum grade on the interstate. Once you're off the interstate, then you might encounter steeper and/or longer grades (6%, 7%, 8%, 9%). If a mountain road is really curvy, then the posted speed limit might be 35 mph. If that's the case, then you might be running 20 - 25 mph towing. The engine doesn't work near as hard at those speeds, thus keeping the oil and coolant temps in good shape.

I feel the throttle get lazy around 245, 260 gets worse, you are pretty limited to 20mph from what I remember at 268 and you are almost finished until the water catches up and hits 248 where the dash is flashing and you are doing 5mph on the shoulder for a couple mins while it cools....Rinse and repeat till you pull over or crest the hill. Seems like I logged 50% load being the max available at 260°. FYI.........I have never seen 268 oil temp, 248 coolant temp, hard derate, or the dash flashing since the last recall reflash.....I assume they pulled out some fuel before that happens?

I can definitely agree that lower speeds are the Eco's friend, but it's just not all that popular to hold up traffic at 20-40mph when the posted speed limit is 55mph and the traffic generally is going 5-15mph over that......This is the case with the 9% grade heading east out of my town.

My solution is to just be off the road when towing heavy by the time the temps exceed 95°. Here in CA posted towing speed limit is 55mph, but even in other states I pretty much cap the speed at 62ish unless there is a tail wind.

 

[fourfa]

I'd get in contact with RPM Extreme and see if their fan controller can work with the diesel.

I did that:

”I have not had a diesel here to read the data and test a controller on.
I have verified it works with the 3.6, 2.0 and for both the GPEC2a and newer GPEC5. Just haven’t had a diesel here to play with yet.“

They’re in Alabama. Anyone nearby?

 

[jav_eee]

I did that:

”I have not had a diesel here to read the data and test a controller on.
I have verified it works with the 3.6, 2.0 and for both the GPEC2a and newer GPEC5. Just haven’t had a diesel here to play with yet.“

They’re in Alabama. Anyone nearby?

Someone should make the trip up there. I feel like the controller would solve everyone’s problem.

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