Does my radiator need to have a transmission cooler?

[Hazieview]

Fixing to order my be cool radiator and I was wondering if it needed the built in Transmission cooler? I already have an external trani cool that will be mounted in front of the radiator. Thanks

[baclay9]

I was told by my tranny builder not to even use the radiator transmission cooler. He said to just run an external cooler. He said he has seen coolant leak over into the trans fluid too many times.

[Hazieview]

Originally Posted by baclay9

I was told by my tranny builder not to even use the radiator transmission cooler. He said to just run an external cooler. He said he has seen coolant leak over into the trans fluid too many times.

I didn't think about that.... that makes since. I was told not to use the trani cooler so I figured I would just get one without a cooler built in it.
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[BigBlocksRule]

Use the external - it'll work a lot better. The ones built into radiators aren't very effective and as earlier comments said, subject to leaks.

[jimbonice]

Water has much greater thermal conductivity and heat transfer properties than air which equates to something like 32 times better. That's not a bit better, or twice as good, it's 32 X as good which is probably valuable insurance for your tranny. I'd run both, first into the external cooler and then into the rad.

[N2TRUX]

Originally Posted by jimbonice

Water has much greater thermal conductivity and heat transfer properties than air which equates to something like 32 times better. That's not a bit better, or twice as good, it's 32 X as good which is probably valuable insurance for your tranny. I'd run both, first into the external cooler and then into the rad.

That may be true, but its not as good as you make it sound. An external cooler is much more effective due to the efficient design. I have used both and prefer external only.

[baclay9]

Since this is on the subject of the OP, what kind of external cooler and about what size do you guys recommend? My builder recommended the tube and fin style but didn't really say what size. He just said "Bigger isn't always better."

[BigBlocksRule]

Originally Posted by jimbonice

Water has much greater thermal conductivity and heat transfer properties than air which equates to something like 32 times better. That's not a bit better, or twice as good, it's 32 X as good which is probably valuable insurance for your tranny. I'd run both, first into the external cooler and then into the rad.

Yeah, but if the water in the radiator is 190+, it really cuts it's cooling efficiency.

[mooseknuckles]

Originally Posted by baclay9

I was told by my tranny builder not to even use the radiator transmission cooler. He said to just run an external cooler. He said he has seen coolant leak over into the trans fluid too many times.

exactly!....use a tranny cooler.

[78 Chevyrado]

The trans cooler in the radiator is just a CHEAP solution. It saved them money on millions and millions of cars and trucks, but like many other things on there, it's a compromise and not necessarily the highest performance piece you can get.

With the trans cooler in the radiator, the best you can hope for is cooling the trans to the same temp as the engine coolant, and that's only if it's 100% efficient.

I have an external cooler on mine.

[Scouten45]

so when is it a good idea to use a trans cooler?

[mooseknuckles]

Originally Posted by Scouten45

so when is it a good idea to use a trans cooler?

all the time!

[jimbonice]

If you check with the shops that build hd tranny's for towing, they recommend to add an external cooler to the factory cooler. Some won't warranty them without the original factory cooler installed in addition to an external. As I stated the factory cooler is pretty efficient and hard to beat. My hemi Ram has both an external and rad cooler from the factory, a lot of modern trucks with the heavy duty cooling options do. There is zero harm for a transmission to operate at normal coolant levels, they're designed for it. The harm is in elevated levels to the point fluid starts to cook and allow clutches, seals etc. to cook. 190 degrees is not the temp they do this. Just my 2 cents and change.
Cheers

[463]

heres a link t a chart http://www.txchange.com/heatchrt.htm

[BigBlocksRule]

190 degrees doesn't boil tranny fluid, but it doesn't wick away much heat, either. The closer the temps, the less cooling you'll get.

[mooseknuckles]

heat kills transmissions.

[Hazieview]

??????
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[lakeroadster]

Since the external cooler doesn't have the 190 F. heat soak of the engine coolant it will be more efficient.

I run an external cooler only on my 350 tranny and have a dedicated tranny temp. gage. Haven't had any problems, been in operation for the last 10 years.

[bigblock73]

Originally Posted by jimbonice

If you check with the shops that build hd tranny's for towing, they recommend to add an external cooler to the factory cooler. Some won't warranty them without the original factory cooler installed in addition to an external. As I stated the factory cooler is pretty efficient and hard to beat. My hemi Ram has both an external and rad cooler from the factory, a lot of modern trucks with the heavy duty cooling options do. There is zero harm for a transmission to operate at normal coolant levels, they're designed for it. The harm is in elevated levels to the point fluid starts to cook and allow clutches, seals etc. to cook. 190 degrees is not the temp they do this. Just my 2 cents and change.
Cheers

You are exactly right, always run your external cooler with the factory one. I have heard this MANY times, in fact, the place I got my OD trans from recommends it as well. Also, for those running only the aftermarket ones, these are often time cheap units as well, and can break down just as easily...then what do you do? IMO, two can't hurt anything, why not run the fluid thru both? I have had more vehicles in my life than I can count, with most being over 10 years old and having over 100K on the odometer...none had aftermarket coolers...and none had transmission problems.

[N2TRUX]

don't really want to debate what the experts have told you guys. I will state that unless you have had a transmission with an accurate temp gauge and compared the temps while under a load, you don't know the difference that an aftermarket cooler makes.

[cr34t3d_by_d4rkd3n]

Originally Posted by jimbonice

Water has much greater thermal conductivity and heat transfer properties than air which equates to something like 32 times better. That's not a bit better, or twice as good, it's 32 X as good which is probably valuable insurance for your tranny. I'd run both, first into the external cooler and then into the rad.

but is that worth the excessive heat the coolant can heat the trans fluid to on on hot summer 115 F days??

[Hazieview]

I think I'm going to go ahead and get a radiator WITHOUT the transmission cooler.

It just make since to me that the fluid will be cooler if it only goes through the external cooler that will be located in front of the radiator.

I will go ahead and install a trani temp gauge if the are not too expensive.

The only thing I wonder about is in the winter....

Is there a such thing as getting the trani fluid too cool?

Shouldn't be that big of a deal here in Texas I dont think but I could be wrong...

[BigBlocksRule]

With the quality of Be Cool versus the plastic junk that comes in new stuff, I wouldn't worry about leaks...if it's not too much more, go ahead and get it with the tranny cooler. You can plug the fittings and then if your external unit doesn't cut the mustard, you'll have the extra cooling from the one in the rad.

[lakeroadster]

I guess whaterever works for you is the right answer...

One advantage to leaving the existing radiator cooler and adding an auxilliary is the added capacity of oil.

An on-line article http://www.carcraft.com/howto/transm...all/index.html from CarCraft states:

Often, external trans coolers are plumbed so that they replace the stock in-tank radiator cooler, but most OE and trans cooler manufacturers recommend retaining the factory cooler, using the external cooler to increase the system's heat-transferring capacity. Proper routing passes the fluid through the radiator cooler first, then on to the external cooler before heading back into the transmission.

And there is also information that supports the above comment that a cold tranny may not be a good thing http://appauto.wordpress.com/2008/01...ssion-issues/:

Another area of cold shift issues, typically delayed shift issues, is the cooling system and related sensors. Most newer transmissions rely on a engine temperature sensor input to determine the proper shift points of the trans during cold operations. Commonly, shift points and are delayed as well as overdrive disabled until the trans reaches full operating temperature. This allows the engine to heat up quicker, transmission to circulate fluid and heat up quicker with minimal stress on the transmission.

The heaviest stress on an auto trans is when the trans is cold and it up-shifts quickly higher gears requiring heavy drive-train load. If you have a bad engine temp sensor, or a thermostat that is stuck open cold, it will provide a simulated cold operation value to the ECU and Trans telling it to continue to delay shift points

Interesting stuff!

[Hazieview]

Originally Posted by BigBlocksRule

With the quality of Be Cool versus the plastic junk that comes in new stuff, I wouldn't worry about leaks...if it's not too much more, go ahead and get it with the tranny cooler. You can plug the fittings and then if your external unit doesn't cut the mustard, you'll have the extra cooling from the one in the rad.

Without Trani Cooler $1,339.95
http://www.summitracing.com/parts/BCI-80313/

Brand Be Cool
Manufacturer's Part Number 80313
Part Type Radiators
Product Line Be Cool Aluminum Power Cooling Modules
Summit Racing Part Number BCI-80313

Radiator Style Crossflow
Overall Width (in) 35.000 in.
Overall Height (in) 21.000 in.
Row Quantity Dual-row
Radiator Finish Natural
Radiator Material Aluminum
Transmission Cooler No
Inlet Location Upper driver side
Inlet Size 1 3/8 in.
Outlet Location Lower passenger side
Outlet Size 1 5/8 in.
Core Height (in) 18.500 in.
Core Thickness (in) 2.000 in.
Core Width (in) 27.500 in.
Tube Size 1 in.
Fan Included Yes
Fan Diameter (in) 13.000 in.
Fan Quantity Dual
Maximum Fan CFM 3,420 cfm
Blade Color Black
Blade Material Plastic
Shroud Color Black
Shroud Material Plastic
Quantity Sold as a kit.


Be Cool aluminum radiator power cooling modules are designed to properly cool your vehicle.

Kits include:

* Aluminum dual 1 in. core performance radiator with oval fluted tubes
* Aluminum fan mounting brackets or straps with hardware (where applicable)
* Diamond-cut, vented coolant recovery tank
* Fan wiring harness(es) with 40 amp relay(s)
* Be Cool billet radiator cap
* One 16 in., dual 11 in., or two 13 in. high-torque Euro black electric puller fan(s) (in selected kits)
* Natural or polished aluminum finish
* Bolt-in installation
* Fan upgrades sold separately



With Trani Cooler $1,694.95
http://www.summitracing.com/parts/BCI-82313/



Brand Be Cool
Manufacturer's Part Number 82313
Part Type Radiators
Product Line Be Cool Aluminum Power Cooling Modules
Summit Racing Part Number BCI-82313

Radiator Style Crossflow
Overall Width (in) 35.000 in.
Overall Height (in) 21.000 in.
Row Quantity Dual-row
Radiator Finish Natural
Radiator Material Aluminum
Transmission Cooler Yes
Inlet Location Upper driver side
Inlet Size 1 3/8 in.
Outlet Location Lower passenger side
Outlet Size 1 5/8 in.
Core Height (in) 18.000 in.
Core Thickness (in) 2.000 in.
Core Width (in) 27.000 in.
Tube Size 1 in.
Fan Included Yes
Fan Diameter (in) 13.000 in.
Fan Quantity Dual
Maximum Fan CFM 3,420 cfm
Blade Color Black
Blade Material Plastic
Shroud Color Black
Shroud Material Plastic
Quantity Sold as a kit.


Be Cool aluminum radiator power cooling modules are designed to properly cool your vehicle.

Kits include:

* Aluminum dual 1 in. core performance radiator with oval fluted tubes
* Aluminum fan mounting brackets or straps with hardware (where applicable)
* Diamond-cut, vented coolant recovery tank
* Fan wiring harness(es) with 40 amp relay(s)
* Be Cool billet radiator cap
* One 16 in., dual 11 in., or two 13 in. high-torque Euro black electric puller fan(s) (in selected kits)
* Natural or polished aluminum finish
* Bolt-in installation
* Fan upgrades sold separately