OP
OP
Keeping coolant and transmission temps under control when towing in the summer heat
- Thread starter Geotrash
- Start date
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OP
OP
That’s exactly how I mounted the Derale on mine. It’s a great cooler with more capacity than the factory cooler. I’ll keep everyone posted as I experiment with changing the plumbing. We’re heading back over the same mountain in exactly a month.
Incidentally, on the way back home today it was hotter outside and the eastbound climb is a little longer and steeper. I hit 266° by the time I got to the top. But she held a steady 212° or so for most of the rest of the trip on a mix of interstate and 2-lanes.
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FYI: I finally got to tow today with my derale setup.
I have the trans fluid going to the radiator first, then thru the derale.
I have the derale fan on a toggle switch so I can control it.
Started out trans temps about 180*ish, then when had to climb first small hill
it got up to 196* and stabilized there. Then went thru a little town and up and down
a couple more small hills. Temp got up to 208*. So I turned on derale fan.
Within a couple miles the temp came down to 202 and stayed there..
Later in the trip, now on interstate at higher speed I let the temp come up
to 212* before I turned on the derale fan. It came down to 202-204* pretty
quick and stabilized there.
So I am happy with my project to take the factory aux cooler out as it was
right behind the edlebrock supercharger intercooler... I kinda figured it was
picking up extra heat right before it returned to the trans...
My ambient temps were about 82*, so not "summer heat" ..yet
Heading to Nebraska for a longer 250 mile trip on thursday, so I'll have more data
As a note: At it's highest, my coolant temp did get up to 212* today on the
interstate with my AC on. Once I slowed down towards home and the fans
ramped up, the temp immediately came down to 199*. So at GMC03 mentioned,
I'll have to get into my programming and ramp up the fans to higher duty cycle
to they'll turn on at highway speeds. In town, the low speed comes on at 202*...
So I'll have to figure out that scenario
I have the trans fluid going to the radiator first, then thru the derale.
I have the derale fan on a toggle switch so I can control it.
Started out trans temps about 180*ish, then when had to climb first small hill
it got up to 196* and stabilized there. Then went thru a little town and up and down
a couple more small hills. Temp got up to 208*. So I turned on derale fan.
Within a couple miles the temp came down to 202 and stayed there..
Later in the trip, now on interstate at higher speed I let the temp come up
to 212* before I turned on the derale fan. It came down to 202-204* pretty
quick and stabilized there.
So I am happy with my project to take the factory aux cooler out as it was
right behind the edlebrock supercharger intercooler... I kinda figured it was
picking up extra heat right before it returned to the trans...
My ambient temps were about 82*, so not "summer heat" ..yet
Heading to Nebraska for a longer 250 mile trip on thursday, so I'll have more data
As a note: At it's highest, my coolant temp did get up to 212* today on the
interstate with my AC on. Once I slowed down towards home and the fans
ramped up, the temp immediately came down to 199*. So at GMC03 mentioned,
I'll have to get into my programming and ramp up the fans to higher duty cycle
to they'll turn on at highway speeds. In town, the low speed comes on at 202*...
So I'll have to figure out that scenario
As a note to geotrash, I've always ran my trans fluid to the radiator first, then
thru whatever aux cooler...
I think it's better to "stabilize" the fluid in all weather conditions
and in hot situations to take the bulk of the heat out first like the oem's have
always done.. Not saying doing just a fluid to air cooler doesn't work...
Just seems more predictable and consistent to do the fluid to water cooler first I(to me)
thru whatever aux cooler...
I think it's better to "stabilize" the fluid in all weather conditions
and in hot situations to take the bulk of the heat out first like the oem's have
always done.. Not saying doing just a fluid to air cooler doesn't work...
Just seems more predictable and consistent to do the fluid to water cooler first I(to me)
OP
OP
Thank you for the data points, Tom. VERY helpful for comparing notes through the experimentation process. And I believe your hypothesis is correct that the cooler in the radiator serves the dual purpose of warming the fluid in colder temperatures and cooling the fluid when it's elevated above coolant temperature significantly, as I'm seeing happen on long, steep pulls. The advantage of the Derale in this scenario over the factory cooler, is that it gets the cooler out from in front of the radiator, and because it's a plate/fin cooler with a fan, it has a higher cooling capacity than the factory cooler, and can cool the fluid effectively while pulling up steep grades at low speeds, as well as at idle in traffic - both scenarios that generate heat in the transmission fluid, for which the factory cooler would struggle.
I'll reroute the pluming this week, and if that doesn't do the trick, I'll send Black Bear my data files and ask for their help to adjust the TC lockup and cooling fan speeds.
On a side note, I find the Derale's thermostatically controlled switch to work fabulously well. Even when hot, it only needs to stay on for a minute or two after shutdown before the fluid at the thermocouple is cool enough to shut the fan off, and I like the hassle-free factor of not having to manually switch it on.
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Well guys I got the cooler and fan installed. It has a 180 thermostat to turn on the fan and it shuts off once the fluid hits 165. Currently hasn’t gotten above 172 so we shall see. Don’t mind the janky punched angle bracket but this thing doesn’t move at all.
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OP
OP
Looks great! Thanks for sharing pics of your install, too.Well guys I got the cooler and fan installed. It has a 180 thermostat to turn on the fan and it shuts off once the fluid hits 165. Currently hasn’t gotten above 172 so we shall see. Don’t mind the janky punched angle bracket but this thing doesn’t move at all.
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Hauled our camper down to the outer banks this weekend. No mountains so never saw transmission temps above 200 on the highway, and only 212 in traffic. Planning to make the mods to the lines this week.
Where did you end up mounting yours again??Looks great! Thanks for sharing pics of your install, too.
Hauled our camper down to the outer banks this weekend. No mountains so never saw transmission temps above 200 on the highway, and only 212 in traffic. Planning to make the mods to the lines this week.
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Hey Brandon, Is your lower grille drilled out ??????
Mine is blocked, I'd have to drill holes in it to get direct airflow - not sure I
need it (yet)
I towed about 600 miles this week. My trans temps would get about
200-207*, I'd flip on the fan and they would drop to 190's in a few miles.
The weather wasn't "hot" out yet, but I did buck a good wind on the way
to my destination(Omaha)
It ran cooler today on the way home as it was less windy and a few degrees
cooler
Mine is blocked, I'd have to drill holes in it to get direct airflow - not sure I
need it (yet)
I towed about 600 miles this week. My trans temps would get about
200-207*, I'd flip on the fan and they would drop to 190's in a few miles.
The weather wasn't "hot" out yet, but I did buck a good wind on the way
to my destination(Omaha)
It ran cooler today on the way home as it was less windy and a few degrees
cooler
So it wasn’t, but I popped out the grille and cut the plastic backing out and then cut out the same area on the bumper. I knew the Denali’s lower grille would allow for airflow if I did that after doing some looking. The big trip starts in the 9th so I’ll let you know how it does! Right now I have constant 12v to the thermostat so I think I’m gunna run a wire for a switch inside so that way I can kill the fan if it’s still running after we stop and I shut the vehicle off.
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