SilverBulletCLS

Below is a link on how to install the Tranny Cooler on your CL-S and how to do a flush of your transmission with what tools you have at home. This method does work but will take some time.

After installing it, I drove the car around for about 15 miles, and noticed that the car shifted much faster, smoother. The car seems to have really liked the new fluid, but also the help of that cooler keeping it cooler. After I got back home, that cooler was extremly hot to the touch. I tried both hoses, the top one which is the HOT in, was VERY VERY HOT, could not keep my finger on it for more than 1 sec, the bottom for at least 3 secs I could hold it on there. It was defintely working.

I hope this convinces alot of others to do this mod, because you need too. Our cars do not have a tranny cooler and the fluid just boils and most likely it causes the tranny to die. It's about a 2-4 hr project.

Enjoy guys, any questions feel free to ask.


http://home.satx.rr.com/silverbullet/tranny.htm link updated 08/20/02

Bitium

Nice info. Thanks for the instructions

JaDia4

way to take one for the team! even though it worked out for you too. good call

drcookie

Great write up !!! I love it. I believe it should decrease the chances of failing tranny.

How well does the tranny cooler hold to the radiator ?

How much does your project cost ?

Cheers !!!

TopGum

too bad you're not an acura engineer! is this similar to the setup ct is running with the sc?

SilverBulletCLS

Tranny cooler isn't going anywhere. It's on really tight.

SilverBulletCLS

I couldn't tell you, I havent seen his.

Road Rage

The TL-S and CL-S do have an oil cooler - it is an efficient liquid to liquid cooler, which is more efficient than a liquid to air such as used here. The boiling point of ATF is way beyond what the operating temps of this tranny measure.

TopGum

ct= comptech. sorry!

SilverBulletCLS

If this tranny has a cooler then it must be mounted inside of the tranny. Because IT IN FACT DOES NOT HAVE A EXTERNAL COOLER ANYWHERE. I looked for a very long time, and have worked on many other cars which have coolers.

randomwalk101

Okay, I think the other user was confused with engine oil cooler and transmission oil cooler. To get the fact straight:

Acura TL/CL does NOT have a transmission oil cooler (stock). It DOES have an engine oil cooler (stock).

This topic is about TRANSMISSION oil cooler. Do not be confused!!

Bitium

I know for a fact that on 99 Tl's have a transmission cooler. Is the bottom part of the radiator. You could easily see the in/out lines to the radiator from the transmission.

SilverBulletCLS

Yep, they do, but not the 5spd Autos.

Road Rage

If you look at the transmission fill hole, in front of it is a silvery looking gizmo that seats into the transmission, and has lines running in and out of it. This is the transmission oil heater and cooler. As I indicated, it is a liquid to liquid type, which is more efficient. It also uses the coolant from the radiator to pre-heat the AT fluid, for faster warm up, better MPG, and reduced emissions.

The '99 had the traditional type of cooler. BTW for the self-proclaimed cooler experts in this thread, the ATF heater is in the shop manual schematic.

Another one bites the dust...

randomwalk101

Yes, I know that...but there is no way coolant at 180-190F in that tiny cooler will be able to cool down the tranny oil enough...With the heat here in Texas exceeding 100F everyday. Ideal tranny fluid temp at optimal condition should be around 200F. There is no way that can happen with stock configuration.

SilverBulletCLS

I am sorry but that little heater/cooler is not more effcient. If it was, then we wouldn't have a problem with our trannies. Let me also tell you why does the MDX, RL, and other Honda autos still have a regular Tranny cooler and ours doesn't?!

Road Rage, like you have been wrong on the oil discussions you are wrong again on this.

We do not have a STOCK TRANNY OIL COOLER. We have the cooler/warmer but it only gets it so cold. Our coolant from the radiator/engine does not get below 180 degrees, or even 200 at that.

TopGum

Not an expert but I do have a question. If the 5sp auto has a "cooler" then why is Comptech recommending a transmission cooler (they are using this same B&M unit) for their supercharger appication? This goes for the present AV6 as well as the yet to be released 3.2?

Road Rage

.5) First their was no cooler in this thread, now we established there is one, but we are playing word games about "cooler/warmer". Splitting hairs a bit.
1) First, who has measured the oil temps in the tranny? Who can state for a fact that heat related lubrication failure is the cause of the tranny problems? No one? Thought so. It may be so, yet everyoneis ofering fixes with no facts.
2 If the CL-S tranny problem has been fixed, then does it have an external liquid to air cooler? It would have to based on the logic in here
3) Sorry, but a liquid to liquid cooler is more efficient - I did not say that it would be more so than adding another cooler, but my statement is fact.
4) Loved the cute quip about my being "wrong" abut oil, as though that is relevant here - love to know where my 10 years of tribology study and professional experience have gone astray,

ngcreese

You know, this whole bad transmission thing bothers me, in a sense. I'm a microchip designer (so no thermodynamics from me unless you want to talk about electron migration or long net hot spots )

We do have a phase in any product development cycle called design verification. Where, we think up scenarios based on past experience, current technological & architectural limits, and anticipated usage of the product.

Extreme cases that push the product to it's braking point we would refer to as corner cases. These usually require some good imagination or at least in Acura's and their bad tranny's case, some good understanding of the demographics of the people buying their cars... my point somebody didn't have a deep enough imagination... (sigh marketing strikes again).

We are falling into what could probably be considered a corner case. We are a bunch of people who like to drive hard on occasion. However, our driving style, I suppose, was not fully anticipated…

I've heard this car referred to in this manner by several people on this board. "...It surely is a sleeper performance car with a lot of potential...." In this case, there is more potential in some parts of the car then others...

Oh well, I guess we'll have to make up for the rest on our own until Acura readjusts it's thinking to take more aggressive driving styles into account. My comptech springs and anti sway bars are perfect examples of making up for one of Acura's shortcomings. The tranny cooler is the other. BTW, in the year and 24K miles of driving the car this is the only major, from the factory, defect I've experienced.

Even with the extras, I still haven't paid as much as I would for a BMW. However, with the BMW 330i I probably wouldn't have to upgrade the sport suspension or cool the tranny more (unless I retuned its engine and got 400hp out of it... and then this whole modification game would start again).

In the mean while, my dealer is swapping my burnt up transmission with a new (rebuilt, I suppose) unit. And, he was kind enough, at my request to install a B&M tranny cooler based on the install instructions in the link above (I bought it, he'll install it at no charge during the tranny swap) .

Even though there is a liquid to liquid heat exchanger on our 2002 TLS, the general consensus on tranny failure seems to point, with high probability, to heat build up in extreme (corner case) conditions. To put it in the words of the service manager, "... it couldn't hurt to have a cooler in there".

I know there are people out there on the fence about this car and are checking out its shortcomings… well this is one. The suspension is another. If you’re almost sold anyway, then go for it! (It is still not that expensive compared to the competition) Just remember, if you think you’re going to drive hard, on occasion (with 260hp, you probably will ) then ask your dealer to install a tranny cooler before you drive off the lot.

“… it couldn’t hurt...”

Sorry for this long gust of wind... ... ...

garylee55

You had me until you started focusing on the 'corner' containing aggressive drivers...I do not fit into this category. I drove my TL no differently than any other car I've ever driven....I never raced it, and I never used the sport shift...

randomwalk101

Perhaps you guy missed my post on the failure of the tranny. The transmission failed partially only because of heat. However, the main reason it failed is because of the shifting mechanism in itself. Acura was trying to make their shifting smooth (overly trying to correct their shifting mech. from Legend), which basically ride on the clutch and let it out so slowly. This burns out the clutch tremedously, creates lots of heat which in turn kills the fluid and other parts, dusts fro the wearing off from all the friction of parts (clutch and others) which goes into little orifices and ultimately ceased up the tranny. The reason people experiences "clutch slipping" before the tranny fails is because the clutch had worned out. Since it is the shifting mech., the tranny will eventually fail regardless of how you drive it (although it is safe to assume that if you drive like you stole the vehicle, that will kill it sooner ...ei. more wear & tear faster). In the end, it is a bad design in all. Tranny cooler HELPS prolong it by cooling the fluid thus cools the parts (and prevent fluid break down and let the fluid does it job), but it does NOT solve Acura design problem.

PAW

They all die one day!

Road Rage

I was going the same direction - I have an EE and Mech Eng degrees, and worked for many years as a liube engineer, then computer process control engineer. One of major issues was determing failure rates, maintenance schedues, etc. which led to the best cost effectiveness between downtime and plant utilization.

There have been enough failures of trannies around granny drivers to suggest that heat is not the proximate cause of the failures. And, I woned three and drove them all hard, and never had problem one. As a scientist, that is just anecdotal, but interesting.

Someone said the problem was fixed int he new CL-S's - what is it? I will betcha that this is a problem of internal parts either not engineered properly or mfd or assembled right. Likely a clutch pack or internal pressure valve. It will be identified and fixed as an ongoing correction, and all rebuilts will at some point benefit. Or, Acura will go to (Aisin or N-D) and demand a new design.

BTW, as a tribologist, I can assure you that it is possible to have the lubricant too cool. All engineered motor or mechanicals in a car are designed to function best at a certain temperature, where the expansion coefficients of parts are homeostatic. Plus, too cool and water vapor does not dissipate in the lube, which can reach with sulfurs and hypochlorides in the air to form corrosives. Trannies like to run in the 160-180 range.

SilverBulletCLS

Your right, trannys like to run in 160-180 degree temps, but if you ever measured ours, its over 220 normally.

TopGum

Tell me if I am wrong but since the cooler install, the tranny is more willing to hold gears. It is more willing to downshift under acceleration and it does not seem to be in such a rush to get to 5th. Bottom line is feels more responsive to driver input. The "feel" of the gear change is the same. It is not any harder or softer.

Road Rage

220 measured WHERE? How?
That is the criticial question 220 at the outlet heading to the cooler is not bad. 220 at the inlet going into the tranny might be. The old "wear rate" tables for trannies were based on the old formulations of ATF - the newer ones have much better resistance to hi temp oxidation, and more anti-wear additives. Most manual trannies now use ATF, where it has to sustain shear forces worse than an autobox. Yet these regularly go over 100k miles. The HFM atf Honda recommends is a very tight formulation.

All I am saying is no one has yet produced evidence that hi temps are the cause of the premature failures, and also, how to explain how only some trannies are affected by high temps, while others (like all 3 of mine) chugged along in Virginia summers without a problem.

One thing I do recommend is to take the car out of gear when at a stoplight - also, a lot of guys on this Forum brake-load the tranny for stoplight drag racing, which heats up the TQ converter dramatically in seconds.

SilverBulletCLS

Correct, I feel the same thing. The cooler the fluid, the faster the belts will shift. Simple. The tranny should have a much better life now. People need to install these.

SilverBulletCLS

Going into the cooler. Out of the cooler was reading 175. Which I liked to see.

220 is way to high, over 200 is when the fluid starts to break down.

Road Rage

I do not think that 220 out of the tranny is way too high - that is about average for engine oil temp, and since the heat exchanger is based on the coolant temp, which is about 195, one would expect that the tranny oil temps would be in that range, about 20 degrees higher. You may be right that the cooler would have some benefit if internal trans problems are causing a bad wear condition and excessive heat, but it is just delaying the inevitable, if indeed there is an intrinsic problem, which I no longer have to worry about, and which i will take others anecdotes that there is.

In spite of my questioning posts, i really do hope the cooler works wonders for you.

SilverBulletCLS

Well per everyone I have talked too, over 200 is too high. Normal tranny temps are 180~.

And this includes tranmission shops.

DHB

Road Rage, why do you no longer have to worry about it? Do you no longer have a TL or CL-S?

EricL

FYI, there is a tranny temp sensor in the actual transmission.

It is a thermocouple. It is possible to get the readings of the tranny right at the ECU.

So, it is possible to get the temperatures inside the transmission.

Given the 50+ HP loss (on a dyno) at full load, the BTU/HRs is immense. Even though the stock cooler is a fluid-to-fluid intercooler, any plate coolers of similar dimension would be swamped with the heat load. (We are talking about a coolant-to-ATF cooler that is the size of hockey puck.)

And, it would be "nice" to get before/after temps in a variety of situations.

Comptech claims that they were seeing some rather extreme temperatures. However, I don't know how and where they were measuring the temps...

Finally, don't be surprised to find some "Bozo" who connects up a overkill ATF cooler that turns the ATF into syrup in an upcoming winter...


$0.02

Road Rage

I sold my TL-S to make room for the Cobra, and bought an Outback for day to day schlepping of the wife and tiny tot. I guess I should go away now? But I like to spread my "rage" around, and I still get PM's here about oil questions from those who do not think I am a poser on lubrication issues.

Good points Eric, of course the load loss is only partially in the tranny internals - frictional and torsional losses also occur in the exterior mechanicals - CV's for one. Yes, the hockey puck is small, but remember that the Corvette liq to liq engine oil coolers were of that type, as is the engine oil cooler on my SVT Cobra, although the coolant connections are huge, and the car also has an external PS cooler. They are quite efficient.

All: let us know how this mod works out for you.