ATF cooler

[vlado11]

I'm thinking about installing an ATF cooler on my '97 Altima. My question is: do I installed it so that the fluid from the feed line enters this cooler first, than the factory one, or should it be installed on the return line to the trans? The second one makes more sence to me but just want to make sure.
Also, is cooler better? Would I benefit if I got one that is little larger than recommended for this vehicle, or would this cause any unnecessary obstruction in the flow of fluid, or excess strain on whatever is pumping the fluid through the coolers?
thx

 

[vlado11]

ups... just realized I posted in the wrong forum.. sory guys. Could someone move this to mechanical/maintenance
thx

 

[Black_Thunder]

factory cooler as in through the radiator?

or a separate fluid to air cooler?

 

[vlado11]

yeah, it has a radiator factory cooler

 

[okiedokie]

I'd put a temp gauge on it 1st if it already has a OEM cooler.

 

[Colt45ws]

Ive always been told to place it after the factory cooler, before it goes back to the trans. Thats where mine is going as soon as I get some fittings and hose...

 

[daman]

Quote:

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I'm thinking about installing an ATF cooler on my '97 Altima. My question is: do I installed it so that the fluid from the feed line enters this cooler first, than the factory one, or should it be installed on the return line to the trans? The second one makes more sence to me but just want to make sure.
Also, is cooler better? Would I benefit if I got one that is little larger than recommended for this vehicle, or would this cause any unnecessary obstruction in the flow of fluid, or excess strain on whatever is pumping the fluid through the coolers?
thx

---

if your talking about the cooler in the rad., i would feed
the aftermarket cooler after the rad. cooler then to the trans..

 

[unDummy]

ATF cooler is good. Whether its before(northerners) or after(southerners) the stock radiator loop isn't something to worry about. You can even run it in parallel with the stock cooling if you tee it in that way.

In the winter, you can simple ductape or cardboard it off to allow reasonable ATF temps. Nissan tends to use temp for shift points. If too cool, no TC lockup = poor highway MPG. Cool fluid also leads to later shift points and different line pressures for shifts. Cold jatcos can be pretty jerky.

A synthetic or blend is also a recommended upgrade.

ATF coolers rarely restrict flow too much. So don't worry about it if hoses and fitting sizes are equal or bigger then your Nissan. Yes, some generic ATF filter kits turn into 'restrictors' due to small hose or fitting diameters, kinked hoses(invest in some 90 and 45 degree fittings), and excessive hose runs(trunk mounted cooler). Stick with the name brand ones and use common sense during the installation.
I also prefer solid fabricated mounting vs. zip ties through radiator.

Since Nissans lack adequate ATF filtration, I'd recommend one of the PH8a/PH977 sized remote ATF filter kits. This way, you'll get that quart+ sump increase, and might even negate the need for that oversized ATF cooler.

A temp gauge would be needed to determine whether the cooler you chose is too big or too small. Since its OBD2, you can monitor the temp with a scanner(palmpilot, laptop with appropriate software/adapter).

 

[vlado11]

thx guys...

unDummy, you're right about the torque converter not locking up in OD untill the ATF reaches almost normal operation temps. This drives me nuts in cold winters when it takes about 20+ minutes of highway cruising (on my way back from work)) before this happens. MPG's suffer big time. I always wondered if there was a way to reprigram the tranny to eliminate this feature. But I guess it is better to be left alone, since I ain't no engineer, and didn't design this tranny

 

[daman]

Quote:

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thx guys...

unDummy, you're right about the torque converter not locking up in OD untill the ATF reaches almost normal operation temps. This drives me nuts in cold winters when it takes about 20+ minutes of highway cruising (on my way back from work)) before this happens. MPG's suffer big time. I always wondered if there was a way to reprigram the tranny to eliminate this feature. But I guess it is better to be left alone, since I ain't no engineer, and didn't design this tranny

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It's designed that way from the factory so your car
warms up faster..

 

[unDummy]

Bypass the stock OEM cooler with a thermostat since the icy cold radiator is doing nothing to warm up your ATF during the winter.

You can parallel splice into the wiring for the ATF temp sender with a resistor(variable and with a switch to disable) and trick the TCU in thinking that the ATF is warmed up. The engine is warm in 5 minutes if the thermostat is working. The AT can take forever to lock the TC.

Because of ATF flow issues, I would not trick the TCM unless a good flowing full synthetic ATF is in use. You'll have seriously sluggish shifting if the fluid isn't moving and the TCM is thinking everyone is warmed up. Even with a full synthetic like M1 or Redline, I'd still would let it warm up for at least 5 minutes before overriding the temp sender.

A defective temp sensor could prevent or delay the TC from locking up if it is failing.

Since your location isn't the north pole, a water:ATF heat exchanger to help warm the ATF with hot engine coolant isn't a feasible option. As you have found out, cold engine radiator isn't optimum for winter use as it can overcool the ATF.

 

[mechtech2]

Trans > radiator cooler > after market cooler > trans.
The radiator cooler helps warm the fluid when cold, and cool it when hot.
All after market cooler mfrs. suggest this routing.
No, it's not perfect, but much better overall.

 

[shoz123]

The radiator cooler will not add heat to the fluid when the ambient air is cold. The ATX cooler is on the "cold" side of the radiator.

 

[mechtech2]

Aftermarket cooler Mfrs. recommend running the cooler AFTER the stock cooler.
Part of the reason is for cold weather and overcooling.

 

[onion]

Just as a matter of preference, I always run the ATF through the aftermarket oil-to-air cooler first, then back through the OEM oil-to-water cooler. My reasoning is that the oil is at its hottest when it first comes out of the transmission... which means that you have maximum temperature differential between the oil and the air- therefore maximum cooling efficiency. Regardless of whether the next cooler (oil-to-water) cools it further, or warms it up a bit (depending on the weather?)... the ATF has lost the maximum amount of heat that it can through the aftermarket cooler- and not directly into the engine cooling system.