Worth upgrading transmission oil cooler?

Edris335i · 12-29-2018, 02:05 PM

Hey guys, so I have a ST N54 and was wondering if I should upgrade the transmission oil cooler? I would get it for a steal installed. Also an automatic tranny. I'm currently at about 102,000 miles. I was also wondering if I should do a ATF drain/fill? I know ZF recommends doing it at about 100,000 but I've read that people say their tranny starts slipping after and I'm afraid of that.

autoart · 12-29-2018, 10:04 PM

Are you tracking the car? The auto fluid gets cooled thought the radiator. What trans cooler are you looking at? Are they the m3 coolers?
I don't see a need unless your racing.
Many have changed the fluid around 100k and been fine. Who knows it might have done before you. I did mine at 85k used Valvoline, and it works great. In fact it shifted even better after. good luck.

Edris335i · 12-29-2018, 10:43 PM

Quote:

Originally Posted by autoart

Are you tracking the car? The auto fluid gets cooled thought the radiator. What trans cooler are you looking at? Are they the m3 coolers?
I don't see a need unless your racing.
Many have changed the fluid around 100k and been fine. Who knows it might have done before you. I did mine at 85k used Valvoline, and it works great. In fact it shifted even better after. good luck.

BMS needs a car for their install guide for their new tranny oil cooler and I was asked by someone I know from there. I might track the car eventually but no plans as of right now.

Boland01 · 12-30-2018, 08:29 AM

I would go for it. I saw that BMS tranny cooler the other day.

Boland01 · 12-30-2018, 08:33 AM

On our 335i and 535i automatics the transmission has an external oil cooler that bolts to the bottom of the radiator to hold it in place.

I prefer this type of cooler to the ones that have the tranny and radiator coolers interconnected. The reason is "if-when" the radiator finally leaks into the built in tranny cooler you will quickly destroy your transmission. a lot of Nissan owners have had that happen to them.

Edris335i · 12-30-2018, 01:40 PM

Quote:

Originally Posted by Boland01

On our 335i and 535i automatics the transmission has an external oil cooler that bolts to the bottom of the radiator to hold it in place.

I prefer this type of cooler to the ones that have the tranny and radiator coolers interconnected. The reason is "if-when" the radiator finally leaks into the built in tranny cooler you will quickly destroy your transmission. a lot of Nissan owners have had that happen to them.

Yeah I want my tranny to survive as long as possible and living in Southern California, the summers can get pretty warm. I'm pretty sure I still have the stock radiator as well so do you recommend getting the BMS one? Most threads that I've read online talk about tracking and spirited driving, which I do often, so I was thinking to just go ahead and get it done but I wanted to see if any automatics on the forum have it and how useful it's been.

Boland01 · 12-31-2018, 09:23 AM

If they are going to heavily discount I'd say go for it. I see Payam is writing installation instructions for it. We live in Houston and the summers get pretty brutal here too. If the connections and routing is good it will definitely help. One of the biggest killers of transmissions is heat. Let everyone know how it works out.

12-29-2018, 02:05 PM	#1
Edris335i First Lieutenant 36 Rep 307 Posts Drives: Jet Black E92 335i Join Date: Jun 2018 Location: Simi Valley, CA iTrader: (1)	Worth upgrading transmission oil cooler? Hey guys, so I have a ST N54 and was wondering if I should upgrade the transmission oil cooler? I would get it for a steal installed. Also an automatic tranny. I'm currently at about 102,000 miles. I was also wondering if I should do a ATF drain/fill? I know ZF recommends doing it at about 100,000 but I've read that people say their tranny starts slipping after and I'm afraid of that.
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12-29-2018, 10:04 PM	#2
autoart Colonel 347 Rep 2,281 Posts Drives: 2009 335i e90 M/ 22 X3 Join Date: Oct 2010 Location: socal iTrader: (8)	Are you tracking the car? The auto fluid gets cooled thought the radiator. What trans cooler are you looking at? Are they the m3 coolers? I don't see a need unless your racing. Many have changed the fluid around 100k and been fine. Who knows it might have done before you. I did mine at 85k used Valvoline, and it works great. In fact it shifted even better after. good luck.
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12-30-2018, 08:29 AM	#4
Boland01 Lieutenant 149 Rep 460 Posts Drives: 2010 535ix, 2008, 2007 335i Join Date: Sep 2013 Location: Magnolia, TX iTrader: (0)	I would go for it. I saw that BMS tranny cooler the other day.
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12-30-2018, 08:33 AM	#5
Boland01 Lieutenant 149 Rep 460 Posts Drives: 2010 535ix, 2008, 2007 335i Join Date: Sep 2013 Location: Magnolia, TX iTrader: (0)	On our 335i and 535i automatics the transmission has an external oil cooler that bolts to the bottom of the radiator to hold it in place. I prefer this type of cooler to the ones that have the tranny and radiator coolers interconnected. The reason is "if-when" the radiator finally leaks into the built in tranny cooler you will quickly destroy your transmission. a lot of Nissan owners have had that happen to them.
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12-31-2018, 09:23 AM	#7
Boland01 Lieutenant 149 Rep 460 Posts Drives: 2010 535ix, 2008, 2007 335i Join Date: Sep 2013 Location: Magnolia, TX iTrader: (0)	If they are going to heavily discount I'd say go for it. I see Payam is writing installation instructions for it. We live in Houston and the summers get pretty brutal here too. If the connections and routing is good it will definitely help. One of the biggest killers of transmissions is heat. Let everyone know how it works out.
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