My trans cooler setup. . .

N54gasm

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Plz shoot me a text 1-631-672-9176

Messaged you.

Where do your trans temp reach when at idle (zero air flow)?

The highest ive seen it at idle (no airflow) when idling for 15ish mins was 163*. This was with temps around 92ish outside.

On a side note, something I did not post in my original post was I drilled a shit load of holes in the splash shield to help airflow.
 
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Notmpwr

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Jul 5, 2017
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I would be careful about the thermostat, most trans coolers don't use them because the trans will maintain an acceptable temp, most anything over 110*f and the fluid will be ok, especially the low viscosity zf lifeguard fluid, same thing as mercon sp.

The problem with the thermostat is it can partially restrict cooler flow thus increasing converter charge pressure and that will result in a engine thrust bearing failure because the converter is pressing against the crank hub because of the high converter charge pressure.
 
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Notmpwr

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Not this thermostat. Its tue most free flowing thernostat ive ever seen. It recircs when closed so it heats up quick and once it reachea temp it opena.
Ok, that's good. I know some restrict flow when in the closed Position. Do you live in a cold climate?
 

doublespaces

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Oct 18, 2016
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Not this thermostat. Its tue most free flowing thernostat ive ever seen. It recircs when closed so it heats up quick and once it reachea temp it opena.
Sorry if I missed it, which tstat do you have? I have the improved racing 165* tstat. Going to trouble shoot it tomorrow actually, may try to take the thermostat off actually.
 

Notmpwr

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Sorry if I missed it, which tstat do you have? I have the improved racing 165* tstat. Going to trouble shoot it tomorrow actually, may try to take the thermostat off actually.

I believe he's running the Earl's.

Personally I never run and don't really hear of many other thermostats in a trans coolers setup because the minimum trans operating temp is so low.

If you lived a very cold climate but anything that doesn't stay in the teens for a majority of the year it's fine without.
 

Notmpwr

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I run the earls yes. I live in a moderate climate, in the winter, RARELY hits the teens and if it does its for a night or two.
.

You could probably ditch the thermostat, if it ever failed or someone else would like to add an external cooler. I think the lower operating fluid temp for the zf lg6 is 100 degrees and it would easily maintain that even in cold climates.

Did you cap off or bypass the factory cooler as far as coolant lines go, or Just leave it in place.
 

N54gasm

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100f is too cold. And without a thermostat, temp would never get up to op temp. With this thermostat, allows the temp to warm up. Even if it sticks closed, fluid still recircs so flow is never interrupted (just does not go through the cooler) and at that point, ill notice as my trans temps would be higher (always monitor the jb4 lol).

And I made a few block off bungs for the stock cooler.
 

Notmpwr

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100°f is the minimum operating temp but not optimal.

I think you'll find that without the thermostat it will indeed get up to the correct operating temp very quickly.

The 6r stuff is at 140-150 by the time the engine is up to temp and honestly everyone is probably not beating on Thier cars when they are cold or at least shouldn't be.

Just tossing that in case someone is trying to eliminate the thermostat for budget or reliability reasons.
 

N54gasm

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Eh, would take longer than that imo. By the time my engine is to op temp, ima round 120-130ish trans temps. And that's with the closed thermostat. Imagine through a large cooler with airflow. . . The thermostat isnt expensive, and definatly aint a reliability issue either but to each their own.
 

chrisdfv

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Aug 29, 2017
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Does it matter which line from the trans, goes to the thermostat? I'm looking to install a cooler soon, and just trying to put everything together in my head. I've already got a cooler, fittings, and lines, but haven't ordered a thermostat. Looks like it seems optimal to just bite the bullet and get a thermostat like yours.
 

JAperformance

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Feb 13, 2017
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Which Tru-cool Cooler are you using? I have a Setrab 16 row with a 165 Improved Racing Tstat
 

b4llistic

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EDIT: Thanks your finding and reading my post. Unfortunately, Spoolstreet is no longer a neutral platform where we can have honest discussions on subjects and products freely.
For this reason I have deleted all information I posted on the forums.
 
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b4llistic

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EDIT: Thanks your finding and reading my post. Unfortunately, Spoolstreet is no longer a neutral platform where we can have honest discussions on subjects and products freely.
For this reason I have deleted all information I posted on the forums.
 
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doublespaces

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Start the car. You'll see the fluid oozing out one of the hoses. The real OEM chart was accurate for me.
Edit: the perspective is the transmission in my testing
 

b4llistic

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EDIT: Thanks your finding and reading my post. Unfortunately, Spoolstreet is no longer a neutral platform where we can have honest discussions on subjects and products freely.
For this reason I have deleted all information I posted on the forums.
 
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