Added transmission cooler (I thought)

[Tyandkate]

I brought my truck in for a oil change and transmission service. While in I decided to have them add a external transmission cooler. So I got the call it was ready. The shop installed a NAPA rapid cool transmission cooler I’ll post a link to it at the bottom of the post here’s my concern.
The cooler was installed in the front of the radiator with a direct path of air. But they bypassed the transmission cooler built in to the radiator. Is this okay or is this going to be a issue while towing? Seeking advice from someone that has more knowledge on the subject. Thanks so much for the advice in advance.

The cooler is 11” wide by 9 1/2” tall 3/4” thick
https://www.napaonline.com/en/p/ATP17510

[Lynnmor]

Gdetrailer wrote:


Water cools down in the radiator and the COOLED water SINKS to the bottom of the radiator..

Just the way gravity works..

Thermosiphon cooling systems are a thing of the very distant past. For example, Farmall Cub tractors used the system back in the early 1950's. Modern engines have a water pump and any effect from thermosiphoning would be minor. See: Thermosiphon

[SidecarFlip]

4 pages of popcorn opinions. I like that. 15 years ago I deleted the plate cooler in the radiator and went external. never had an issue, trans temps never higher than 190. Fluid always looks and smells good on every annual change (with filter) and the pan is always clean... I happen to change mine every year.

What works for me, may not for you, but for me, I'm happy.

[babock]

joshuajim wrote:
Since the external trans cooler is located in front of the engine radiator, the air going into the engine radiator could be 200 degrees instead of 100 degrees. So how does this improve the engine cooling?

The temp difference is not that great.

[theoldwizard1]

1320Fastback wrote:
Never bypass the stock radiator cooler. Transmission fluid that is too cold is just as bad as overheated fluid, normal engine temperature is ideal for the transmission fluid.

Most modern transmissions have a thermostat ao too cold is not really an issue.

[joshuajim]

badsix wrote:
in cool temps its not going to be a problem ether way. its when your pulling a long mountain pass in the middle of August with the outside temperature around 100 deg. your radiator cooler is already near 200 deg engine temp. then your trans starts to heat up pushing the engine temp up more then external cooler has to take care of both sometimes not being able to handle it. I would think its a good idea to bypass the radiator cooler as they did. that keeps the trans heat out of the radiator and in the axillary cooler.
Jay D.

Since the external trans cooler is located in front of the engine radiator, the air going into the engine radiator could be 200 degrees instead of 100 degrees. So how does this improve the engine cooling?

[Gdetrailer]

marcsbigfoot20b27 wrote:

Gdetrailer wrote:

lawrosa wrote:

LarryJM wrote:

lawrosa wrote:

Its 8f here in NJ now. If I didnt have the rad cooler the trans would never get warm. In this cold it barely gets over 110f. But if I idle, it warms it up.

The increase in your tranny temp has ABSOLUTELY NOTHING to do with the rad cooler which as I said in my original post WILL NEVER WILL WARM THE TRANNY FLUID regardless of how cold it is outside.

Larry

Nonsense.. If I start my truck and not drive it at all the trans temp with come up to engine temp exactly 190f.. So How is my trans warming up??? Its simple matching the coolant temp..

But when moving the coolers come into play. So as you saw in my video I had 230 coolant temps and a 175 trans temp... Because i'm moving and have a massive cooler..

Be aware that the "coolant" temps you are reading are from the engine block, not the radiator. Typically the coolant temp sensor will be near where your upper radiator hose attaches to the engine which also is where your Thermostat lives..

Coolant temp at the top of the block AND radiator will typically MUCH hotter than the bottom of the radiator and block..

So, you can easily have 230 reading on the top of the engine and 210-220 at the top of the radiator and only have 190-200 at the bottom of the radiator and block..

Top of engine block retains more heat due to large metal mass than the top of the radiator (small metal mass)..

Water cools down in the radiator and the COOLED water SINKS to the bottom of the radiator..

Just the way gravity works..

You can prove that theory the next time by adding a few remote thermometer sensors.. One at the top of the radiator and one at the bottom..

While you are at it, do the same with transmission lines..

The results will be a surprise to you that your large extra external cooler is shedding only 10-30 F..

Yes, shedding even 10 degrees F can help prolong your transmission life so it is not all that bad of an idea, but overall not always going to help.

Not quite sure about your cold water sinks deal since most radiators are cross flow design now.
I have always wondered however what the delta is between the hot water tank side of the radiator @ ~200F and the cold return side of the radiator after the air has cooled it...

My extra large trans cooler (6.0 diesel) was 3 times larger than the OEM 7.3 cooler. Before towing up big mountains at 110F ambient was 225F and now it is NEVER over 165F ever. That is a 60 degree difference, so they do work but its all about size and design.

Crossflow radiators STILL do the same thing, cooler water will sink to the bottom of the cold side tank, Trans cooler loop is on the cold side of the tank closer to the BOTTOM of the tank..

If gravity didn't work there would be no need to put HOT side connection HIGH and and the COLD connection low would there..

I have yet seen a trans cooler loop placed on the top of the radiator tank or at the top of a side tank of a crossflow..

[marcsbigfoot20b]

Gdetrailer wrote:

lawrosa wrote:

LarryJM wrote:

lawrosa wrote:

Its 8f here in NJ now. If I didnt have the rad cooler the trans would never get warm. In this cold it barely gets over 110f. But if I idle, it warms it up.

The increase in your tranny temp has ABSOLUTELY NOTHING to do with the rad cooler which as I said in my original post WILL NEVER WILL WARM THE TRANNY FLUID regardless of how cold it is outside.

Larry

Nonsense.. If I start my truck and not drive it at all the trans temp with come up to engine temp exactly 190f.. So How is my trans warming up??? Its simple matching the coolant temp..

But when moving the coolers come into play. So as you saw in my video I had 230 coolant temps and a 175 trans temp... Because i'm moving and have a massive cooler..

Be aware that the "coolant" temps you are reading are from the engine block, not the radiator. Typically the coolant temp sensor will be near where your upper radiator hose attaches to the engine which also is where your Thermostat lives..

Coolant temp at the top of the block AND radiator will typically MUCH hotter than the bottom of the radiator and block..

So, you can easily have 230 reading on the top of the engine and 210-220 at the top of the radiator and only have 190-200 at the bottom of the radiator and block..

Top of engine block retains more heat due to large metal mass than the top of the radiator (small metal mass)..

Water cools down in the radiator and the COOLED water SINKS to the bottom of the radiator..

Just the way gravity works..

You can prove that theory the next time by adding a few remote thermometer sensors.. One at the top of the radiator and one at the bottom..

While you are at it, do the same with transmission lines..

The results will be a surprise to you that your large extra external cooler is shedding only 10-30 F..

Yes, shedding even 10 degrees F can help prolong your transmission life so it is not all that bad of an idea, but overall not always going to help.

Not quite sure about your cold water sinks deal since most radiators are cross flow design now.
I have always wondered however what the delta is between the hot water tank side of the radiator @ ~200F and the cold return side of the radiator after the air has cooled it...

My extra large trans cooler (6.0 diesel) was 3 times larger than the OEM 7.3 cooler. Before towing up big mountains at 110F ambient was 225F and now it is NEVER over 165F ever. That is a 60 degree difference, so they do work but its all about size and design.

[beemerphile1]

transmission out - radiator - auxiliary cooler - transmission in

[lawrosa]

Gdetrailer wrote:

lawrosa wrote:

LarryJM wrote:

lawrosa wrote:

Its 8f here in NJ now. If I didnt have the rad cooler the trans would never get warm. In this cold it barely gets over 110f. But if I idle, it warms it up.

The increase in your tranny temp has ABSOLUTELY NOTHING to do with the rad cooler which as I said in my original post WILL NEVER WILL WARM THE TRANNY FLUID regardless of how cold it is outside.

Larry

Nonsense.. If I start my truck and not drive it at all the trans temp with come up to engine temp exactly 190f.. So How is my trans warming up??? Its simple matching the coolant temp..

But when moving the coolers come into play. So as you saw in my video I had 230 coolant temps and a 175 trans temp... Because i'm moving and have a massive cooler..

Be aware that the "coolant" temps you are reading are from the engine block, not the radiator. Typically the coolant temp sensor will be near where your upper radiator hose attaches to the engine which also is where your Thermostat lives..

Coolant temp at the top of the block AND radiator will typically MUCH hotter than the bottom of the radiator and block..

So, you can easily have 230 reading on the top of the engine and 210-220 at the top of the radiator and only have 190-200 at the bottom of the radiator and block..

Top of engine block retains more heat due to large metal mass than the top of the radiator (small metal mass)..

Water cools down in the radiator and the COOLED water SINKS to the bottom of the radiator..

Just the way gravity works..

You can prove that theory the next time by adding a few remote thermometer sensors.. One at the top of the radiator and one at the bottom..

While you are at it, do the same with transmission lines..

The results will be a surprise to you that your large extra external cooler is shedding only 10-30 F..

Yes, shedding even 10 degrees F can help prolong your transmission life so it is not all that bad of an idea, but overall not always going to help.

Yeah I wondered that in the aspect of where does the temps get read from... As with the added trans gauge in the cluster I believe its a sensor directly in the transmission...

I did have to change the coolant sensor and its on mid block near spark plugs on opposite side of engine and the coolant return/t stat..

The results will be a surprise to you that your large extra external cooler is shedding only 10-30 F..

Yes, shedding even 10 degrees F can help prolong your transmission life so it is not all that bad of an idea, but overall not always going to help.

I have to disagree here.. I dont know how it cant help.. And reading here about guys having 240 trans temps is insane...Im fine with 200f max, ( although I never saw it)

This was the start of that massive 8 minute climb in NC to mile high campground.. Temps started at 190 and 160 trans. Towards the top like my other video I was 230 and 175 trans.. I wonder what I would be without the cooler...


And thats the trouble with 3:42 rears and a 4 speed.. It wasnt long before first gear 3500 rpm and 30 mph... But I can pull all day I think but its just slow going... I was at probably 5500 lbs trailer. probably 12500 - 1300 total GCWR..

This was also with A/C running...

I thought I did well for a 2006 with 88k miles on the OD..

But like anything else everyone has their own opinions..

Like giants vs jets, or ford vs chevy...


https://www.flickr.com/photos/93289479@N04/39374259561/in/datetaken/

[Gdetrailer]

lawrosa wrote:

LarryJM wrote:

lawrosa wrote:

Its 8f here in NJ now. If I didnt have the rad cooler the trans would never get warm. In this cold it barely gets over 110f. But if I idle, it warms it up.

The increase in your tranny temp has ABSOLUTELY NOTHING to do with the rad cooler which as I said in my original post WILL NEVER WILL WARM THE TRANNY FLUID regardless of how cold it is outside.

Larry

Nonsense.. If I start my truck and not drive it at all the trans temp with come up to engine temp exactly 190f.. So How is my trans warming up??? Its simple matching the coolant temp..

But when moving the coolers come into play. So as you saw in my video I had 230 coolant temps and a 175 trans temp... Because i'm moving and have a massive cooler..

Be aware that the "coolant" temps you are reading are from the engine block, not the radiator. Typically the coolant temp sensor will be near where your upper radiator hose attaches to the engine which also is where your Thermostat lives..

Coolant temp at the top of the block AND radiator will typically MUCH hotter than the bottom of the radiator and block..

So, you can easily have 230 reading on the top of the engine and 210-220 at the top of the radiator and only have 190-200 at the bottom of the radiator and block..

Top of engine block retains more heat due to large metal mass than the top of the radiator (small metal mass)..

Water cools down in the radiator and the COOLED water SINKS to the bottom of the radiator..

Just the way gravity works..

You can prove that theory the next time by adding a few remote thermometer sensors.. One at the top of the radiator and one at the bottom..

While you are at it, do the same with transmission lines..

The results will be a surprise to you that your large extra external cooler is shedding only 10-30 F..

Yes, shedding even 10 degrees F can help prolong your transmission life so it is not all that bad of an idea, but overall not always going to help.

[lawrosa]

I put the hayden 12x12 in...And feeding stacked plate coolers from bottom there is in theory air issues.. IDK if true... I lowered the factory cooler to get it out of the way of the big bow tie on the grill.. was blocking air flow.. And I purposely mounted the added cooler on its side... Feeding from the bottom up, then back to the trans..

Just another FYI...

https://www.amazon.com/gp/product/B000C3BBKS/ref=oh_aui_detailpage_o09_s00?ie=UTF8&psc=1

[lawrosa]

Tyandkate wrote:
So question for everyone thanks so much for the advice. I’m going to get this fixed ASAP in the next couple of days I do have some work I’m going to have to use my truck for not pulling the camper but a trailer of 1000 pounds or so. Will this current set up be okay for the time being not driving over 60 miles or so?

If its a 1500 and you have the 4 speed 4l60e then ran in 3rd gear. Its direct drive there and will make way less heat then trying to stay in overdrive... I tow in 3rd all day long... 9 mpg.

If you have tow haul use it as it also keeps the Torque converter locked up as long as it can... Less heat...

I showed you real world results... You decide

[lawrosa]

LarryJM wrote:

lawrosa wrote:

Its 8f here in NJ now. If I didnt have the rad cooler the trans would never get warm. In this cold it barely gets over 110f. But if I idle, it warms it up.

The increase in your tranny temp has ABSOLUTELY NOTHING to do with the rad cooler which as I said in my original post WILL NEVER WILL WARM THE TRANNY FLUID regardless of how cold it is outside.

Larry

Nonsense.. If I start my truck and not drive it at all the trans temp with come up to engine temp exactly 190f.. So How is my trans warming up??? Its simple matching the coolant temp..

But when moving the coolers come into play. So as you saw in my video I had 230 coolant temps and a 175 trans temp... Because i'm moving and have a massive cooler..

[lawrosa]

Tyandkate wrote:
I’d love to know how you added that transmission temp guage it looks factory.

Sent the cluster out to a place in Connecticut. For $225 they replaced all bulbs, stepper motors, and added the trans gauge.. I did have to drive without a cluster for about a week... Ummm I am not sure what they made for 2001.. They do 03-06 I think...


https://www.fixmygauges.com/conversions-and-upgrades.html

[ScottG]

There's a good chance the cooler in the radiator does a better job than the extra one they installed. Water conducts BTU's nearly 1000 times better than air.
I would make them fix it and certainly don't tow with it the way it is.