Q45 automatic trannie cooler

Post by **jamesmost** » Mon Jun 14, 2004 4:56 am

Need some help i have a 95 Q45, just purchased a trannie coolermuch to my surprise there are 4 lines on the heat exchanger (2 in and 2 out) i need to know: 1- how to hook up the cooler ? 2- which lines are feed lines and which are return lines? 3- do u bypass the the stock heat exchanger completely?thanks much

Post by **elwesso** » Mon Jun 14, 2004 4:56 am

check out my website, http://www.q45.org for my writeup... I did the transmission cooler.....

Goto the tech help section

Post by **jamesmost** » Mon Jun 14, 2004 4:56 am

ok checked out ur stuffstill confused what year is ur car? did it have 4-lines on the radiator??

Post by **Q45tech** » Mon Jun 14, 2004 4:56 am

Early Q had single exchange later had duals one on each end tank because they realized one was not enough.

The hottest one will be the passenger side of radiator.

Select how what you want to do.........I would place the auxillary air to ATF cooler in the transmission return line and leave much of oem system intact. Cur the metal line after the combining tee and series the new cooler their with supplied hoses.

Remember the main oem purpose was to heat the ATF up fast to 176F not to provide much more cooling than the 180-190F coolant temperature. But in summer the coolant can go to 220F and nothing but new air is cooler..........even behind the condenser the air gets to 140-150F.

Post by **jamesmost** » Mon Jun 14, 2004 4:56 am

so what u r saying is:run the cooler on the passenger side lines and cap off the lines on passenger side (which is the return side)??

Post by **jamesmost** » Mon Jun 14, 2004 4:56 am

also what is up w/that external trannie filter to the left and behind radiator never saw it befor

Post by **Q45tech** » Mon Jun 14, 2004 4:56 am

The transmission filter is designed to catch the smaller particles that the internal filter doesn't. Another improvement. But they get plugged and go into bypass if not changed every 60k........just something to reduce in warranty failures.

Why plug the unused in rad lines?

The problem is things are in parallel [to avoid the previous problem of the single unit plugging up and reducing flow.

Mix and match conundrum.......parallel or series or both and the effects of each..........depends on the transmission outlet temp what you want to do..............meditate on it.........make some measurements and decide.........doesn't make much sense to cool the ATF so the in radiator heat echangers can warm it back up......thus the final return line after all the heating has occurred.

Post by **PalmerWMD** » Mon Jun 14, 2004 4:56 am

Most here just bypass the factory heat exchanger entirely .I had it like that on this Q and the 2 previous ( the third previous suffered early transmission demise due to clogged factory heat exchanger).

Fred..

Post by **jamesmost** » Mon Jun 14, 2004 4:56 am

how do i bypass it if there r 4 lines

Post by **maxnix** » Mon Jun 14, 2004 4:56 am

PalmerWMD wrote:Most here just bypass the factory heat exchanger entirely .

I didn't based on my observations of ATF fluid condition at flush time. I put my coolers after the heat exchanger on the theory even if heat was gained from the coolant, the auxiliary cooler would thereby somewhat reduce the engine cooling load before it was returned to the transmission.

In reality, I believe from what I have been told that the ATF is almost always hotter than the coolant in summer, hill, or high engine power demand driving. This would explain in part why the later 1994-1996 G50 (in combination with the external filter) does so much better than the earlier 1990-1993 G50, which were modified several times to cope with problems caused by overheated fluid.

In AZ, there probably is a strong argument for bypassing the OEM heat exchagers entirely. However, I saw only a very slight (barely discernible) change in color of my fluid on a car that had been used primarily to drive from TX to the CO mountains in the summer, or to the coast. It had only the dealer drain and replace for the first 52K miles.

Post by **elwesso** » Mon Jun 14, 2004 4:56 am

I completely bypassed the stock heat exchanger and the filter...

Chop all 4 lines, and take out the filter, then hook the 2 lines up to the transmission cooler, and your done! Couldnt be easier!

If you put it in between the radiator and condensor, on the drivers side, it will have plenty of airflow, and slightly heat the ATF in the winter time.. I guess you need to go much easier on the transmission for it to warm up when its really cold, but in AZ you shouldnt have to worry about that.....

Ive noticed my car runs slightly cooler with the external ATF cooler in place......

Post by **Q45tech** » Mon Jun 14, 2004 4:56 am

"slightly cooler". How would that be, heat from ATF cooler heats the air in front of rad and that hotter air transfers less from coolant in rad.

Conservation of energy rule [LAW].

Now if you were to put the AT cooler somewhere not in the air flow of rad. Anyway the AT creates so little heat compared to engine ----inconsequential.

Just like wetter water raises the coolant temp [a degree or 2F] by taking more heat from the heads.....thus combustion chamber temp drops.[the important thing].....to complicated for the layman so they lie and say the coolant temp drops. Instead of explaining the Physics.

If you bypass the oem filter get something in line to replace it.

Post by **maxnix** » Mon Jun 14, 2004 4:56 am

I would kindly suggest that the Infiniti engineers put the external ATF filter in the later G50 for a reason, and I would certainly suggest that anyone examines the design of any OEM part that someone else recommends omitting.

Secondly, I would also check that someone's credentials and qualifications to make such a recommendation.

Most of the advice posted on this board (especially Q45tech) is well considered and responsible. Otherwise, it should be subjected to careful consideration.

Post by **elwesso** » Mon Jun 14, 2004 4:56 am

There are kits on summit racing things that have a filter kti that uses regular cheapo oil fliters, for like $20.....

Post by **PalmerWMD** » Mon Jun 14, 2004 4:56 am

Bypassing the stock heat exchanger in its entirety, is crucial to eliminating it as a possible choke point ,for ATF flow.

At the age of our vehicles, more often than not they have become clogged (something the engineers likely did not consider, as luxury vehicles in japan, are retired at low milages.)

I have owned (and driven HARD in HOT weather) 3 Q45's with the stock set-up completely bypassed.One of which was in MN.

f I would be surprised, if frequent ATF exchanges, dont negate the need for that filter also.

Fred...

Post by **Q45tech** » Mon Jun 14, 2004 4:56 am

As changing the ATF every 20,000 miles does nothing to protect against the grinding away that flaked off friction material creates, particles smaller than the holes in the metal internal screen filter.

Every addition cost money to add and everything helped a little , takem together they significantly improved the transmission life..durability.

Post by **elwesso** » Mon Jun 14, 2004 4:56 am

I still think that if Fred thinks its ok, you do regular pan drops, and change the fluid, youll bef ine withouth the filter

I only had a TINY bit of stuff in the bottom (and could have be metal shavings from cutting it open with the hacksaw), and i know my transmission had no maintenance up to 118k... Has had 2 flush/fluid changes from 119k to 128k...

In addition, you can take out the external ATF cooler MUCH MUCH easier and clean it out..

There is a narrow range of particles that will not get caught by the magnet and not get caught up by the screen, the screen is very tightly meshed, so big chunks wont get through.. The shavings will get caught by the magnet, i probably had about 2mm of junk built up on the magnet.. Even when I had it in the parts cleaner and not complete cleaning it (lunch break), there was MORE metal stuff that came up on it.. That puppy is STRONG!

With this, I take comfort running with no filter.. It may not be ideal, but Im unconvinced it will do any major damage by not having it... Besides, the sooner my transmission fails the sooner I can get 90-93 transmission!

Post by **maxnix** » Mon Jun 14, 2004 4:56 am

I would think that the filter is designed to catch the worn clutch materials in the fluid. Hence, heat exchanger clogging is reduced significantly.

My Q45 are all under 65k, so I do not fear heat exchanger clogging.

I agree with Dennis.

On this one, I will still defer to the Nissan engineers. I certainly don't know better than they do.

Post by **Q45tech** » Mon Jun 14, 2004 4:56 am

Heavy trucks have multiple filters [series and parallel] everywhere!They even filter the coolant, diff fluid, power steering, compressed air for brakes.Everything is filtered and filtered again.So much cheaper to change filters every 6 months than to change any hard part.

What would be nice would be a clear filter housing so you could see what happens when the car is off and the ATF drains without pressure.

http://www.jag-lovers.org/xj-s....html

Post by **maxnix** » Mon Jun 14, 2004 4:56 am

Great link, Dennis. Now I have something else to do, 3 times over.

Post by **wlong** » Mon Jun 14, 2004 4:56 am

This discussion has made me curious.

Q45Tech may know the answer; but I would expect the flow to the cooler to be warm coolant right out of the working parts (clutches, etc.) of the transmission, potentially contaminated with debris. In other words, the internal screen only screens the ATF before it goes to the transmission - not necessarily just before the cooler. Therefore, the in-line ATF filter will protect the OEM cooler from clogging.

On the other hand, if the cooler flow is just a parallel flow path to bleed and cool the fluid, it may be fairly clean.

Does anyone know if the filter/ cooler path is full flow?

My car has the stock setup and I am trying to decide what to do like everyone else.

ThanksW. Long

Post by **jamesmost** » Mon Jun 14, 2004 4:56 am

SO WHERE IS THE BEST LOCATION FOR EXTERNAL COOLER1-BETWEEN RAD AND COND2-bEHIND WHEEL WELL3-LEFT OF DRIVER SIDE HEADLIGHT4-IN FRONT OF WHERE FILTER BOX USED TO BE

Post by **elwesso** » Mon Jun 14, 2004 4:56 am

Radiator and condensor..... That eliminates the need, IMHO, to route it inline with the heat exchanger.....

Post by **jamesmost** » Mon Jun 14, 2004 4:56 am

IMHO? i hear you wes i still think that location may be self defeating, also i just posted the lumbar info check it out

Post by **elwesso** » Mon Jun 14, 2004 4:56 am

I dont see how it could be self defeating..

It will keep the cooler WARM but it will still cool

You dont want the fluid getting TOO cold... This controls the amount of air flow... I dont see a better place to put it....

Post by **maxnix** » Mon Jun 14, 2004 4:56 am

Q45tech's post is why I prefer it out of line with the radiator and condenser. Hard to get cooling there unless it is first, then shed heat load is transferred to (or more accurately, cooling flow is reduced) to the following heat exchangers. Also, under the left wheel well it is well protected besides getting generous airflow. Lastly, this location allows the use of the B&M 70264 cooler that has 30% higher capacity than the 70268.

elwesso wrote:I dont see how it could be self defeating..

Maybe it should be IMBO?

Post by **jamesmost** » Mon Jun 14, 2004 4:56 am

the 70264 fits in all those locationsmax do u have a cooler mounted?if so how is trannie in the winter??

Post by **Q45tech** » Mon Jun 14, 2004 4:56 am

The maximum pressure in the cooler lines from the TC is 30 psi.Members mistakenly believe the cooler then directly feeds the transmission pan. It does not!

The output of cooler feeds the rear planetary gears and the transmission middle then drips into the pan where the pump sucks it up....splits the flow 3 ways to other sections and the TC input.

The cooler only sees 4 quarts per minute of flow.........while the pump may flow 2-3 times that amount.

So it takes 2-3-4 passes thru the cooler to cool or filter all the 10 quarts of ATF....[4 quarts per min].......once every 2.5 minutes.............this is 3 times faster than Toyota uses on LS400.

{interestingly the SAE testing standard requires 4.5 quarts per minute of flow 0.086 +- 0.003 L/sec}http://www.swri.edu/4org/d08/A...f.pdf

The airflow past the transmission and transmission pan, the multibolt connection to the bell housing and to engine block is all a serious part of overall cooling...........the engine block should be no more than 200-220F........so that is relatively cool.

Most SAE test ATF to 272F for a max of 70 hours or until failure.

Another test uses 93.3C [181F] for 10,000 cycles

http://neptune.spacebears.com/....htmlh ... age25.html

Post by **maxnix** » Mon Jun 14, 2004 4:56 am

jamesmost wrote:the 70264 fits in all those locationsmax do u have a cooler mounted?if so how is trannie in the winter??

Check Member's Rides under my username. All mine are mounted in series for the reasons stated above.

I live in only mild winters areas. Don't believe a 70264 will fit between condenser and radiator because of its thickness.

Q45tech wrote:http://www.perma-cool.com/Catalog/Cat_page25.html

Interesting Perma Cool shows the cooler and filter installation in series. I wonder where the ATF temperature sensor is installed?

Post by **jamesmost** » Mon Jun 14, 2004 4:56 am

i did not mount mine yet but i had it in there it does fit

Q45 automatic trannie cooler

Q45 automatic trannie cooler

trannie cooler

Maybe Yes, But Definitely No In My Installations

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