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current hot rod: CTS-V
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Discussion Starter · #1 ·
Will running the trans lines strait to the cooler give me enough cooling or should I also run through the radiator?

This is for a 200-4R, stall speed around 2400rpms. The cooler is an $80 Heavy Duty Perma-Cool 1.5"x7"x18", 21,000GVW. It will be placed in front of the radiator on my Caprice, so it will get plenty of air.
 

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Use both, putting the aftermarket cooler in series with the internal rad cooler. Make sure the fluid goes thought he rad cooler last as it will warm the temp of the fluid back to operating temperatures on colder days. Remember being to cold is almost as bad as being to hot. Like engines transmissions have an optimum operating temperature as well
 

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I am leaning towards just running an auxilary cooler on my 74 Coupe. In part because the transmission in it is burned up and I do not want to mess with flushing the tranny cooler already there. There aren't that many really cold days here.

I have also considered replacing the entire radiator. If I do that I would run it in series.
 

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I have driven hunderds of thousands miles, many have been under towing conditions. I have had the tranny lines running every different combination possible and could not documment any problems with any of them. I put 207,000 miles on a straight cooler with no problems so I think your tranny will survive longer than the car if you run driectly to the add on cooler.

Trees
 

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My truck does not have a built in rad cooler, so I just use the auxillary cooler. Been there 10 years without a problem, towing trailers etc.

If you have both, however, why not use them?
 

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current hot rod: CTS-V
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Discussion Starter · #6 ·
I have to make all new lines, I figured it would easier to go strait to the cooler.

poncho62 said:
My truck does not have a built in rad cooler, so I just use the auxillary cooler. Been there 10 years without a problem, towing trailers etc.

If you have both, however, why not use them?
 

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the rodder
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There's absolutely no need to run your lines thru the radiator as well. For your car/engine, the cooler is just fine. Placing the cooler in front of the radiator will downgrade the efficiency of the radiator. However, this has no bearing on any passenger car, unless you'd drop a rat motor in your Caprice. If you want to do make up for the loss of radiator exposure, get a Permacooler with a fan for the hot days. Too cold ATM fluid only becomes an issue when you install a reservoir (B&M Environmental Control System), then you'd have to plumb in line a temperatur control valve as well. Only for racing.

Happy plumbing...

Fred:thumbup:
 

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trees said:
I have driven hunderds of thousands miles, many have been under towing conditions. I have had the tranny lines running every different combination possible and could not documment any problems with any of them. I put 207,000 miles on a straight cooler with no problems so I think your tranny will survive longer than the car if you run driectly to the add on cooler.

Trees
Do you have any facts to support this:rolleyes:

fredsbackyard said:
There's absolutely no need to run your lines thru the radiator as well. For your car/engine, the cooler is just fine. Placing the cooler in front of the radiator will downgrade the efficiency of the radiator. However, this has no bearing on any passenger car, unless you'd drop a rat motor in your Caprice. If you want to do make up for the loss of radiator exposure, get a Permacooler with a fan for the hot days. Too cold ATM fluid only becomes an issue when you install a reservoir (B&M Environmental Control System), then you'd have to plumb in line a temperatur control valve as well. Only for racing.

Happy plumbing...

Fred:thumbup:
Over cooling is always an issue when the tranny never gets to normal operating temperatures condinsation continues to build and is evaporated out.

Back in the mid 90's some new wonderboy engineers decided it would be cheaper to just run an external cooler instead of the in rad cooler in a few different models. The result, lots of burnt up trannies, lots of them up here in the great white north. The reason for it was decided to be that on very cold days the tranny fuild was waxing( becoming to thick to flow). The best part of the whole thing was that the fix was...you guessed it installing an internal rad cooler. Alot of people seem to get stuck on the "if a little bit is good alot most be better sydrom" even with cooling. Just like an engine a transmissions has an opimum temperature to last the longest to cold or to hot will have a negative impact on its life.
 

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The newer metric trannys 2004r 700r4 4l60`s suffer from overheating! cars with hot cams generate more engine heat,so if you run both the cooler and radiator cooler and you should overheat the engine ?you will overheat the tranny? I suggest using just the auxiliary cooler, if you get some cold days just let the engine warm up and take it slow until you get the temp up. I will ad that I see a huge difference in trannys that use a stand alone cooler they last twice as long! also Gm suburbans with towing paks are also using this type of system FROM THE FACTORY!
 

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ronb said:
The newer metric trannys 2004r 700r4 4l60`s suffer from overheating! cars with hot cams generate more engine heat,so if you run both the cooler and radiator cooler and you should overheat the engine ?you will overheat the tranny? I suggest using just the auxiliary cooler, if you get some cold days just let the engine warm up and take it slow until you get the temp up. I will ad that I see a huge difference in trannys that use a stand alone cooler they last twice as long! also Gm suburbans with towing paks are also using this type of system FROM THE FACTORY!
I'm trying to make some sense of this post how ever from what I can gather you first state that the 4l60(700r4) suffers from over heating problems. Nothing infact could be father from the truth if anything they will run cooler do to their lock-up converter.

Next you state that cars with hot cams generate more heat which isn't exactly true, hight performance engines (high comp turning, high rpm exc) tend to generate more heat how ever if your gonna build such an engine your cooling system should be up to the job. A high performance engine shouldn't run any hotter than a stock engine assuming the cooling system is adiquite. Lol in any case if the engine was hot enough to over heat the tranny you have bigger problems. I highly doubt that you will find any stand alone coolers in rv's that aren't thermastatically equipt for the reason I mentioned in my previous post. As for trannies with stand alone systems lasting twice as long that is just assinine.:rolleyes:
 

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the rodder
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Of course they would say that. Most of the aftermarket coolers are not even up to the task of withstanding the pressure of a transmission. A race tranny runs on 180-210 PSI. Most of the aftermarket coolers can take max. 175-180 psi peak pressure or were not peak pressure tested. Most warehousedealers will not even be able to say what pressure there various brand coolers can withstand. There's only one from Permacool that has been tested up to 300 psi, and one from B&M that will take permanent abuse @200 psi. Earl's has got the full range of coolers. Point I try to make is: for anyone who's never set up an entire transmission cooling circuit from scratch (which will include other components like temp. control valves, check valves, temp. probes etc) the advice to stick with the radiator built-in cooler is probably well placed (most of these feature turbulator fins which makes very efficient cooling). However, from a purely technical point of view, there's no need to run the tranny oil thru the factory rad cooler. HD race coolers are much more efficient and the serious builder would have the cooler/circuit performance tested (Sonnax gear etc) before actually using it. At the end of the day it's all just how serious you would want to go about it.

Fred:thumbup:
 

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The reason for the radiator tranny lines serve two purposes. First, to heat up the tranny fluid from the coolant, to bring the fluid to operating temperature. Second, to cool the tranny fluid down to operating temperature. The transmission will last longer if you have the lines go to the cooler, to the radiator, to the transmission. To not have it hooked up like that, IMO, would be dumb.
 

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I have seen 100 psi in cooler lines of an automatic, never seen much over that. I've never had an aftermarket tranny cooler come apart or leak unless it was damaged in some way.

I've run stand alone tranny coolers for years with out the radiator cooler in the cooling system of the tranny. It does not get real cold where I live in Arizona though.
 

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current hot rod: CTS-V
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Discussion Starter · #16 ·
Crosley, I was waiting for the King of Transmissions opinion.

Thank you everyone for the advice, I received differing opinions from many members I respect immensely. It does get very cold out here. I am somewhat impatient and will probably jump in the car, let it run idle for 30 seconds, put it in gear and go on several cold mornings. For that reason I will run through the radiator and the cooler, only to help the trans warm up on cold mornings.

You guys are great.

Mike
 

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the rodder
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OIL PRESSURE READINGS

Just a comparison of oil pressure readings TH400 vs TH350 (normal range, stock tranny, no engine /tranny mods):

N - Brakes applied - Engine @ 1000RPM: 55-70 PSI / 68-88
D - Brakes applied - Engine @ 1000RPM: 60-90 PSI/ 68-88
Intermediate or LO, Brakes applied,
Engine @ 1000RPM: 135-160 PSI/ 89-111
R - Brakes applied - Engine @ 1000RPM: 95-150 PSI/ 102-134
D- 30 MPH, Brakes released, Engine @3000 RPM, then
close throttle, reading @ 2000 -1200 RPM 55-70 PSI/ 68-88

Correction:

Sorry guys, I was talking rubbish. Cooler line pressure reads much lower. According to B&M cooler line pressure AFTER the cooler can read up to 125 PSI steady. That's why their ECS is tested up to 200 PSI. Depending on how restricting the cooler is, peak pressure readings BEFORE the cooler could be somewhat higher still.
 

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The pressures listed by fredsbackyard look like main line pressure readings.

Main line pressures are not the same as cooler line pressures.

I have run the main line pressure in a 2004r & 4L60 way over 230 psi
 

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NYOFP4RJ3CHRIS
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Crosley said:
The pressures listed by fredsbackyard look like main line pressure readings.

Main line pressures are not the same as cooler line pressures.


I wonder if every tranny he works on has problems with low pressure 'cause he's tapping into the cooler line............:drunk:
 
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