Have had tranny cooler for over a year...

[Huskymaniac]

I am still torn as to whether or not to install. Will it really make a difference on a 96? My mechanic has said we should leave well enough alone.

[svxcess]

I never saw the need to put a cooler in my 96. I got my car with 42,000 miles and in the 10 years I've had it, never saw transmission problems or heat.

And it gets warmer down here than where you are.

Believe me, if I saw even the slightest need, it would be in there. OT has connected the SSM countless times and the tranny temps were always good.

.

[svxfiles]

Originally Posted by svxcess

I never saw the need to put a cooler in my 96. I got my car with 42,000 miles and in the 10 years I've had it, never saw transmission problems or heat.

And it gets warmer down here than where you are.

Believe me, if I saw even the slightest need, it would be in there. OT has connected the SSM countless times and the tranny temps were always good.

.

On YOUR SVX, John!
Most of the SVXi that come here have transmission temperatures right at or over 200°f!
I have one customer that had transmission temps in the 240°f range.
He came back later for a cooler in parallel with the stock in radiator cooler and the transmission temperatures went down to 176°.
If we can control the temperatures on our two most expencive parts, the engine and transmission, then they should last alot longer.

[svxcess]

Well said, Tom

I highly trust and respect his considerable expertise in this area. Had he ever seen the slightest indication that I needed to install a cooler, I would have installed one without question.

What size is your cooler. You want adequate reduction in cooling, while allowing the torque converter to still lock up.

.

[svxfiles]

On another hand Tony,
I just drove my son Nick's 96 4.44 SVX 1602 miles from Abilene Texas, to Wiley Ford West Virginia with no TQ lock up, and only third for high gear.
4000 RPM at about 60 MPH.(about 27 hours driving time)
I/We ues BG Prouducts full synthetic ATF,
Mobil1 10/30 in the engine with a L30165,
and Mobil1 75/90 in the front and rear differentials.
When his trans lost fourth gear , IN Abilene, all I did was to hook up the SSM, and (later when I thought of it) pump up the tires to 40/35.
The transmission was at 198°f for 99% of the trip, with a couple of 207°f spikes when I had to go faster to not get run over.
Only once did I see 208°f, for a minute.
Back down, crank the heater to cook me.
The 4.44 in his SVX is from a 1996 Subaru Outback, and I BELIEVE that he has no external transmission cooler.
I DO KNOW that he does not have an external transmission filter.

The trip just reminds me that we should ALL have synthentics,
just in case.
It never hurts to have an edge, or an out!

[Huskymaniac]

As you can see in my signature, I have synthetics all around now. The reason I am asking about the cooler is that I need an oil change soon and I am also due for the next drain and refill on the ATF. If I were to install the cooler, this might be a good time to do it as I won't be doing another ATF drain and refill soon.

[svxfiles]

I know and respect your knowledge of lubricants.
It far excedes mine.
But unless you know what YOUR cars' actual working temperatures are,
(or pressures are)
then you do not really know whether you need the extra cooler or not.
The guy with the 240° temps,
this was after we had changed to synthetics!
If you are going to Reading we can run the SSM ang get an actual number.

[Sean486]

Originally Posted by svxfiles

I know and respect your knowledge of lubricants.

Really, how well do know?




Sorry couldn't resist.

[benebob]

Originally Posted by svxfiles

But unless you know what YOUR cars' actual working temperatures are,
(or pressures are)
then you do not really know whether you need the extra cooler or not.
.

Normal operating temps for subaru spec atf is 140-170 degrees. I have never been in one that ran in that range reguarly without a cooler in any season in PA except winter. Anything higher than 170 you are causing the fluid to break down quicker then normal and unless more frequent atf fluid chnages are used you will be doing damage to your tranny over the long term.

Why don't you just play darts in the dark boys without a proper gauge placed properly in the hotest fluid area that is all you are doing.

[Huskymaniac]

Originally Posted by svxfiles

I know and respect your knowledge of lubricants.
It far excedes mine.
But unless you know what YOUR cars' actual working temperatures are,
(or pressures are)
then you do not really know whether you need the extra cooler or not.
The guy with the 240° temps,
this was after we had changed to synthetics!
If you are going to Reading we can run the SSM ang get an actual number.

What vintage tranny was that 240 degree reading on?

The SSM idea at Reading sounds like a great idea Tom, I would appreciate that! And if they are too high, Nate can install the cooler as I am sure he will be travelling with his garage-in-a-van again.

[Huskymaniac]

"Some" people might want to become educated by doing some of that reading thing:

http://www.autoshop101.com/forms/AT06.pdf

Things which are important:

1. Operating temperture combined with oil change interval (even somewhat elevated temperatures are Ok if you change the fluid more frequently)
2. Fluid viscosity index (you don't want the viscosity to change a lot over temperature...see article)
3. Shear resistance, which is indicated by the viscosity under the high shear, high temperature test (HTHS)
4. Anti-foaming additive used
5. Anti-oxidation additive used
6. Types of base oils used and their percentages

Not every oil breaks down at the same rate. Not every oil transfers heat at the same rate. Synthetics oxidize slower, shear less, have a higher viscosity index and, sometimes, have superior heat transfer (esters). So Tom is correct in that synthetics help. Mike (LAN) has suggested in the past to use Subaru ATF with Lubegard. That is also a good suggestion as Lubegard adds esters which improve heat transfer and reduce frictional wear but it also adds other fluids which reduce the rate of oxidation (ageing). So, no, not even a gauge can tell you everything you need to know. The only way to truly know what is happening is to send your used oil for a used oil analysis which will tell you how much acid is in the fluid, how much base material is left and what the viscosity sheared to. Or one could ask people what their experiences were (failure rate, fluid color or odor change, etc.) given the model year of the car, the fluid they used, the interval with which they changed the fluid and how they drove the car. I have heard several people suggest that the later model trannies don't need the cooler and, if anything, they can just be an annoyance by delaying or preventing TC lock up.

If you don't want to use an additive like Lubegard and you don't want to change your petro based ATF for 100,000 miles then, yeah, you need to keep your tranny tempertaures down to 170F.

[benebob]

Originally Posted by Huskymaniac

"Some" people might want to become educated by doing some of that reading thing:

http://www.autoshop101.com/forms/AT06.pdf

Things which are important:

1. Operating temperture combined with oil change interval (even somewhat elevated temperatures are Ok if you change the fluid more frequently)
2. Fluid viscosity index (you don't want the viscosity to change a lot over temperature...see article)
3. Shear resistance, which is indicated by the viscosity under the high shear, high temperature test (HTHS)
4. Anti-foaming additive used
5. Anti-oxidation additive used
6. Types of base oils used and their percentages

Not every oil breaks down at the same rate. Not every oil transfers heat at the same rate. Synthetics oxidize slower, shear less, have a higher viscosity index and, sometimes, have superior heat transfer (esters). So Tom is correct in that synthetics help. Mike (LAN) has suggested in the past to use Subaru ATF with Lubegard. That is also a good suggestion as Lubegard adds esters which improve heat transfer and reduce frictional wear but it also adds other fluids which reduce the rate of oxidation (ageing). So, no, not even a gauge can tell you everything you need to know. The only way to truly know what is happening is to send your used oil for a used oil analysis which will tell you how much acid is in the fluid, how much base material is left and what the viscosity sheared to. Or one could ask people what their experiences were (failure rate, fluid color or odor change, etc.) given the model year of the car, the fluid they used, the interval with which they changed the fluid and how they drove the car. I have heard several people suggest that the later model trannies don't need the cooler and, if anything, they can just be an annoyance by delaying or preventing TC lock up.

If you don't want to use an additive like Lubegard and you don't want to change your petro based ATF for 100,000 miles then, yeah, you need to keep your tranny tempertaures down to 170F.

Who reminds you to breath every couple of seconds? Your knowledge is mind-blowly ignorant. I can see darkness coming over the whole east coast.

Highest temp I saw on my SVX for an average pan fluid temp was over 250 degrees without a properly mounted cooler, with a cooler 218 which when I returned home the Mobil 1 synth. that was in it (which at the time had the highest independently verified flash, fire and thermal breakdown limits). That was on a 95 SVX. Don't believe me, that's fine, just keep driving. I'll win this one.

[oab_au]

Gee a lot of technical "what ifs" here.
Just fit the air cooler in series with, and before the water cooler.
The air cooler removes the high end temp, and the water cooler stabilizes the temp for the box to operate properly.

Harvey.

[Huskymaniac]

Originally Posted by benebob

Who reminds you to breath every couple of seconds? Your knowledge is mind-blowly ignorant. I can see darkness coming over the whole east coast.

Highest temp I saw on my SVX for an average pan fluid temp was over 250 degrees without a properly mounted cooler, with a cooler 218 which when I returned home the Mobil 1 synth. that was in it (which at the time had the highest independently verified flash, fire and thermal breakdown limits). That was on a 95 SVX. Don't believe me, that's fine, just keep driving. I'll win this one.

Hmm, forgive me if I don't assume that your experience is typical. I will defer to people whose opinion I actually trust/respect because they don't act like obstinate children. I bet they drove and maintained their cars like, um, adults. I will defer to those people and those Toyota folks that wrote the article I posted. Let's see, whose knowledge is more ignorant...Toyota engineers or some obnoxious dude from pennsyltucky? I have not forgotten that you once insisted that flash points were not flash points even after I posted links to datasheets and pointed out that the claimed numbers were verified by oil analyses from companies like Blackstone. More to say? I'm sure you do.

[Huskymaniac]

Originally Posted by oab_au

Gee a lot of technical "what ifs" here.
Just fit the air cooler in series with, and before the water cooler.
The air cooler removes the high end temp, and the water cooler stabilizes the temp for the box to operate properly.

Harvey.

You are right Harvey, there are a lot of what ifs. But I am not inclined to get too crazy with the decision to address all of them. I was hoping people would provide personal experiences that would unveil a concensus of sorts. Crazy thought, I know.

For example, you propose to put the cooler in series before the radiator cooler. Your point about temperature stabilization with regards to TC lockup makes sense. But, on the other hand, others have been pretty adamant that the main problem with these trannies is pressure, not temperature, and that bypassing the radiator cooler is more desirable due to the much reduced flow resistance. If true, the main reason to use an external cooler is to realize this bypass arrangement, not to reduce operating temperature. I recall the argument being that abuse and/or poor maintenance and/or design flaws lead to a loss of a line pressure which leads to slipping/damage which, eventually, manifests itself as overheating. People propose this sequence of events as opposed to overheating causing damage. The cooler, if all of this is true, is not used to cool an already damaged tranny but to avoid it becoming damaged in the first place. One quandry is that a non-damaged tranny should be running cool enough (given sufficiently short fluid change intervals) and an additional cooler, run in bypass or parallel, would/could make the tranny run too cool.

I am curious to see what my current operating temperatures are if I get to reading and take Tom up on his offer. But I can say that my car takes quite a long time to get to TC lockup temperature in cool, not cold, air temperatures so I don't suspect it is running very hot. Also, each time i have done a drain and refill, the fluid looked pristine and didn't smell any worse than new stinky ATF.