Transmission cooler PLUS radiator?

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7milesout

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It's amazing the crap I don't know. I tend to learn what I learn really well, but never venture outside of that and learn anything else. That's where you geniuses (or is that geniuii) come in.

The ole Scamp seems to want to puke every fluid. So now I'm dealing with the coolant. As I've been having a bit of a coolant leak that I couldn't tell from where. But it looked like about 2/3rds of the way down on the fan side of the radiator. So I pulled off the radiator and took it to a recommended radiator repair shop. They showed me their process procedure and equipment. And pressure tested it. Turns out it was fine where I thought, but the top part near the radiator cap had a crack and was leaking. So, I guess the coolant was running down the radiator making me think the leak was 2/3rds the way down. He said it would be an easy fix.

While there, I was talking to him about the transmission cooling part of the radiator. He said he thought it was better to run the transmission fluid there, especially in times of idling in traffic (which I will rarely or never do, as this is not a daily driver). My Scamp has a transmission cooler below the radiator and it is obvious it is not original with the car.

My question is … would I be better to plumb the transmission lines into the radiator in addition to the auxiliary cooler? Or just leave it as is?
 
Depends on if it's a stock transmission build/converter or or aftermarket. For stock, the transmission cooler in the radiator is fine. But for high stall converters or extra transmission heat, use both together in series. Plumb the fluid to air cooler in downstream of the radiator transmission cooler.
 
Agree with #2 , however , in those days and in today's vehicles whatever the factory installed was done to be just good enough . The bean counters won out over quality every time . There is no harm in adding an auxilliary cooler to your transmission . the greatest enemy of an automatic transmission is heat . I am of the opinion that you can't overcool an auto trans . If the trans runs too cool you can always put something in front of the cooler to raise the temp some . My Scamp has a B&M supercooler mounted in front of the rad and plumbed with stainless -6 hoses . I'm kinda' the guy that overdoes things but my pro built 727 is very happy . JUst a thought .
 
Extra cooling can not hurt.

I go through the radiator first, then through the auxiliary cooler, then back to the transmission.
 
Run the trans through BOTH the radiator and the aftermarket cooler.
This ensures the trans gets up to operating temp as quickly as possible, and also stays cool when needed.
 
Yes, since it’s already in place use the secondary cooler. I’ve never seen an automatic run too cool either. Since the radiator is already out, get the cooler checked and cleaned out. A leak in a transmission radiator cooler is a very bad thing and to be prevented at all cost.
 
OK, I'll have the trans cooler part of the radiator checked as well. They probably will, but I'll make sure. My thinking turns out to agree with what you guys are saying. My thought is that, if the fluid went through the cooler first and then through the radiator, it might GAIN some heat in the radiator (depending on conditions).

But with the other way around, it might not blow off a ton of heat in the radiator, and then it will further cool in the cooler. Sending optimally cooled fluid to the transmission. And that the radiator would tend to warm up the fluid more quickly than just driving alone. Then once the fluids are all fully warm, the radiator is going to tend to cool the trans fluid to a uniform temp before sending to the cooler. I can't think of anything negative.

However, now I'm going to have to find fittings. As I recall, it looked like threaded nipples on the radiator.


7milesout
 
Just a friendly note; Last fall I took a radiator to a radiator shop for repair. Picked it up a few days later, 128.00. In just how I don't trust anyone to play right... I stuck my compressed air nozzle to one of the trans line fittings. Sure enough, the trans cooler was full of water. His NASTY dunk tank water.
 
7milesout said:
It's amazing the crap I don't know. I tend to learn what I learn really well, but never venture outside of that and learn anything else. That's where you geniuses (or is that geniuii) come in.

The ole Scamp seems to want to puke every fluid. So now I'm dealing with the coolant. As I've been having a bit of a coolant leak that I couldn't tell from where. But it looked like about 2/3rds of the way down on the fan side of the radiator. So I pulled off the radiator and took it to a recommended radiator repair shop. They showed me their process procedure and equipment. And pressure tested it. Turns out it was fine where I thought, but the top part near the radiator cap had a crack and was leaking. So, I guess the coolant was running down the radiator making me think the leak was 2/3rds the way down. He said it would be an easy fix.

While there, I was talking to him about the transmission cooling part of the radiator. He said he thought it was better to run the transmission fluid there, especially in times of idling in traffic (which I will rarely or never do, as this is not a daily driver). My Scamp has a transmission cooler below the radiator and it is obvious it is not original with the car.

My question is … would I be better to plumb the transmission lines into the radiator in addition to the auxiliary cooler? Or just leave it as is?
Click to expand...


Here is what I did. Parts numbers included

What Are You Doing To/With Your Car Today?
 
7milesout said:
OK, I'll have the trans cooler part of the radiator checked as well. They probably will, but I'll make sure. My thinking turns out to agree with what you guys are saying. My thought is that, if the fluid went through the cooler first and then through the radiator, it might GAIN some heat in the radiator (depending on conditions).

But with the other way around, it might not blow off a ton of heat in the radiator, and then it will further cool in the cooler. Sending optimally cooled fluid to the transmission. And that the radiator would tend to warm up the fluid more quickly than just driving alone. Then once the fluids are all fully warm, the radiator is going to tend to cool the trans fluid to a uniform temp before sending to the cooler. I can't think of anything negative.

However, now I'm going to have to find fittings. As I recall, it looked like threaded nipples on the radiator.


7milesout
Click to expand...

That's how I plumbed it, trans ---> radiator ---> B&M cooler ---> trans.
 
The transmission cooler fittings are flare fittings so you need a flare to hose barb fitting. I try to use as much of the metal hard-line as possible and only use rubber from one side of the radiator cooler to the secondary cooler and then rubber back on to the metal line after doing this with it.
 
think about it...running transmission fluid through a 180 degree rad is heating it and it is necessary for colder weather operation.
The transmission scientists all say to keep your rad (and engine coolant) at least 180 degrees to prevent wear.
If your build is mild and you don't spend a lot of time going through the big end at wot keep it simple and just run your transmission fluid through your rad.
 
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Depends on the conditions and service of the vehicle. I usually don't worry about extra cooling for a stock transmission and converter in day to use with mostly normal usage. Once things start getting a little more performance or load oriented, though, I view it as a necessity, and always necessary with a performance torque converter. No such thing as over cooling one with a high stall converter, a lot more concerns with just trying to keep it from scorching fluid and melting down.
 
Garrett Ellison said:
The transmission cooler fittings are flare fittings so you need a flare to hose barb fitting. I try to use as much of the metal hard-line as possible and only use rubber from one side of the radiator cooler to the secondary cooler and then rubber back on to the metal line after doing this with it.
Click to expand...

Maybe, maybe not. A lot of radiators have NPT (pipe threads) in the radiator itself, then an adapter screwed in for the metal tubing/flare to attach to. The NPT threaded holes make it easy to attach any kind of hose/tubing you want directly to the radiator.
 
maybe maybe not....
I had a warm 340 with a 9 1/2 dynamic converter that stalled at 3000.
I used a 5" x 11" external plate cooler and did not use the rad heater.Driving the car reasonably hard on a hot day i struggled to get the fluid above 160 degrees and i don't think that was good for the transmission.
I was measuring with one of those heat guns ( i know, they are very inaccurate)
But a heavy vehicle, towing or racing would be different.
 
part of it depends on where you live and how you use the car. if you're in Canada. and drive in winter, that sucker needs some help warming up. i always run a large cooler here in Los Angeles, and bypass the radiator. need cooling in summer more than help warming up in winter
 
This is along the same lines as the clutch fan and shroud. The original design were not a shot in the dark. There is a reason the cooler lines route through the radiator. Even if its 90-100 degrees outside, the trans is still not at it's operating temp. Routing it through the radiator brings it up to temp quickly, preventing slippage/damage. If it's higher performance than stock, it may need help keeping cool, but that does not eliminate the advantage of a faster warm up...
 
There are thermostatic valves that will keep the fluid in the radiator circuit then opens to add the auxiliary circuit when a certain temp is reached. Best of both worlds.
 
I guess I need to add that the Scamp has a 360 that makes maybe 310 hp at the crank. I don't know if that's cold, lukewarm or warm. But it certainly isn't hot. I'm guessing that's lukewarm.

Within this year, I hope to have it make a solid 350 hp at the crank. But 95% of the time it's just a lazy street car. And I believe the trans to be all stock. It shifts firm. But not hard. I would have to believe that the firmness is period correct. Nowadays auto trans shift all slushy.

As a long term goal, I'm going to slap a nitrous plate on it, and probably run a 75 ~ 100 hp shot. Just for giggles. I was hoping to get to that done by the end of this year. But, as you guys know, the problems don't just stop happening. And I'm not doing anything to it (power wise) unless all problems have been resolved and is otherwise solid. I've stopped the gas puking. And I think the engine oil puking. I think the trans pan puking is at a minimum. Now I'm trying to shore up the coolant and trans cooler puking. I think one of the lines to the aftermarket cooler my be leaking at the hose clamp. Will try to confirm either tonight or over the weekend. My garage floor is an awful mess. I dry it up, but between this car and the RX-7 I had before, it's very stained.

The kind of problem a car guy wants to have.


7milesout
 
In my time of trucks I used to day Dodge stood for Drips Oil, Drops Grease Everywhere. While somewhat true, I never had a problem with oil more being more than a 1/2 quart low between being changed or having to add vital fluids back more than they needed to be changed... A vehicle that marks its territory isn't a bad thing, usually just a sign of being used properly for it's intended purpose.
 
while OEM was well engineered, it was also made for a huge variety of conditions, that a lot of people here have decided to not subject their cars too. if someone's only driving the car in good weather that makes warm up less critical.
if your not running a gauge, you're just guessing...
 
7milesout said:
My question is … would I be better to plumb the transmission lines into the radiator in addition to the auxiliary cooler? Or just leave it as is?
Click to expand...
As probably said before, (I didnt read it all)
Plumb the transmission oiled lines into the transmission cooler of the radiator FIRST, then route the cooling line into the external transmission cooler SECOND.

The reason of this route is the stock trans cooler in the radiator cools it down first. The radiator is hot at around 200*’s. The now cooler transmission fluid goes to the much cooler external secondary cooler which is in front of the hot radiator getting the outside cool air first making it the coldest spot in the system. From there, it goes back to the transmission.

FWIW, a transmission loves cool fluid and quick firm shifts. But that’s not what the general public likes. The public likes smooth soft shifts as not to rock there coffee/soda and slide there hamburger to the back of the seat bouncing off the seat onto the floor. They seem to get upset with this.
 
7milesout said:
It's amazing the crap I don't know. I tend to learn what I learn really well, but never venture outside of that and learn anything else. That's where you geniuses (or is that geniuii) come in.

The ole Scamp seems to want to puke every fluid. So now I'm dealing with the coolant. As I've been having a bit of a coolant leak that I couldn't tell from where. But it looked like about 2/3rds of the way down on the fan side of the radiator. So I pulled off the radiator and took it to a recommended radiator repair shop. They showed me their process procedure and equipment. And pressure tested it. Turns out it was fine where I thought, but the top part near the radiator cap had a crack and was leaking. So, I guess the coolant was running down the radiator making me think the leak was 2/3rds the way down. He said it would be an easy fix.

While there, I was talking to him about the transmission cooling part of the radiator. He said he thought it was better to run the transmission fluid there, especially in times of idling in traffic (which I will rarely or never do, as this is not a daily driver). My Scamp has a transmission cooler below the radiator and it is obvious it is not original with the car.

My question is … would I be better to plumb the transmission lines into the radiator in addition to the auxiliary cooler? Or just leave it as is?
Click to expand...

Due to my transmission not being able to shed the higher temps cause when making multiple drag racing passes, I run my fluid from the transmission, to a pair of ball valves. One leads the flow through the radiator and on through a pair of 6 by 12 plate coolers plumbed one after another and back to the transmission. This insures quick warm up and cooling for normal daily driver use.

For racing, I alternate the ball valve positions, which bypasses the radiator and goes directly through just the plate coolers. This keeps the fluid as cool as its going to be during multiple hard passes.

The small brass ball valves were inexpensive and positioned to allow the fluid to warm up quickly during my daily driving adventures, and be switched to bypass the hot radiator during racing. Simple and super easy to change from one setting to the other.
 
jbc426 said:
Due to my transmission not being able to shed the higher temps cause when making multiple drag racing passes, I run my fluid from the transmission, to a pair of ball valves. One leads the flow through the radiator and on through a pair of 6 by 12 plate coolers plumbed one after another and back to the transmission. This insures quick warm up and cooling for normal daily driver use.

For racing, I alternate the ball valve positions, which bypasses the radiator and goes directly through just the plate coolers. This keeps the fluid as cool as its going to be during multiple hard passes.

The small brass ball valves were inexpensive and positioned to allow the fluid to warm up quickly during my daily driving adventures, and be switched to bypass the hot radiator during racing. Simple and super easy to change from one setting to the other.
Click to expand...

You guys are beating this to death !! LOL
 
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