How to: Transmission Cooler Installation

**Opie** · #1: 08-17-2005, 10:01 PM

Here it is:

Transmission Cooler Installation.pdf

**melayout** · #2: 08-17-2005, 10:07 PM

Opie,

Thanks for the guide, looks like an easy DIY with the right tools.

Now some Qs, since it is possible to tow with a USDM Legacy, can Subaru dealers install and warranty the transmission cooler?

Will having the cooler installer by someone else than the dealer void my powertrain/transmission warranty? Will the dealer give me grief about it?

**GTLegs** · #3: 08-17-2005, 10:09 PM

GREAT write up, you did a good job, and the cooler looks like its supposed to be there!! awesome

**Opie** · #4: 08-18-2005, 05:14 AM

Quote:

Originally Posted by melayout

Opie,

Thanks for the guide, looks like an easy DIY with the right tools.

Now some Qs, since it is possible to tow with a USDM Legacy, can Subaru dealers install and warranty the transmission cooler?

Will having the cooler installer by someone else than the dealer void my powertrain/transmission warranty? Will the dealer give me grief about it?

No prob!

I'm sure there are dealers that would install a transmission cooler but unfortunately Subaru does not carry a "factory" add-on transmssion cooler for any model except the new Tribeca so more than likely any warranty would be from the dealership themselves and/or the transmission cooler's manufacturer.

As with any accessory or add-on part a dealer could give you grief about it, but like anything else they would need to prove that the transmission cooler directly caused a failure in order to deny a warranty claim.

**wukindada** · #5: 08-18-2005, 05:47 AM

I'll be doing this very soon, which model Hayden did you use?
1676
1677
1678
Would the 1678 just be overkill on our vehicles? I was planning on purchasing the 1677.

**SVXWRX** · #6: 08-18-2005, 06:06 AM

when installing the tranny cooler, this is also a good time to install an external tranny filter and temp gauge.

the Permacool external filter kit (~$40, Summit Racing, etc.) uses a regular spin-on oil filter, and has a receptacle for a temp sender to make installing a temp gauge pretty easy.

**Opie** · #7: 08-18-2005, 09:47 AM

Quote:

Originally Posted by wukindada

I'll be doing this very soon, which model Hayden did you use?
1676
1677
1678
Would the 1678 just be overkill on our vehicles? I was planning on purchasing the 1677.

I used the #1676, the 1678 is probably overkill...and might be a little cramped in the space.

**AWD-Turbo** · #8: 08-18-2005, 04:25 PM

Thank you very much for this excellent walk through.

I plan on buying the 1676. It should have plenty of cooling capacity for my car now and into the future. I would also be concerned about blocking too much air from the radiator.

**REM87O** · #9: 08-18-2005, 04:51 PM

Opie - I thought there was an external filter on the tranny anyway? Is this right?

Quote:

Originally Posted by SVXWRX

when installing the tranny cooler, this is also a good time to install an external tranny filter and temp gauge.

snip

**tora** · #**10:** 08-18-2005, 05:43 PM

The leg tranny cooler is within the rad, uses the same unit, just plumbed out to the tranny. Our installations go inside the fan so nothing is cut through the rad, it is not visible at all and it is getting fan blown air for city driving. Just a different idea if people want to try that.

**Opie** · #**11:** 08-18-2005, 07:14 PM

Quote:

Originally Posted by REM87O

Opie - I thought there was an external filter on the tranny anyway? Is this right?

The transmission does have an external filter, it is screwed to the side of the transmission and looks like an oil filter.

**firedawgs** · #**12:** 08-18-2005, 08:09 PM

Correct me if I am wrong, but our 5EAT already has a transmission cooler. I was under the hood one day and saw what looked like one.

**melayout** · #**13:** 08-18-2005, 08:24 PM

It is integrated into the radiator, meaning the ATF fluid flows into tubes inside the radiator and radiates its heat into the radiator coolant.

Not very efficient since it is a liquid-to-liquid heat exchange compared to a dedicated transmission cooler with a liquid-to-air heat exchange.

**Opie** · #**14:** 08-18-2005, 08:47 PM

melayout is correct, the factory cooler (built into the radiator) will only cool the transmission fluid as cool as the radiator is (typically 190-210 degrees). An external transmission cooler is more efficient and cools the fluid better.

**REM87O** · #**15:** 08-18-2005, 08:48 PM

Thanks for the post and instructions Opie. Good info.

Now I have another potential mod to add to the list.