Can I run a transmission cooler under normal driving conditions?

[Anthony .]

The only concerns I’ve heard about is the initial warming of the transmission fluid from dead cold, which is why you normally run the extra cooler in line with the existing cooler line in the radiator.

The radiator cooler will heat the fluid up quicker on a cold start and the external cooler will shed off more excess heat once the system is already hot.

My thinking though is that scenario of requiring quick heating is probably mostly related to North America or Europe where sub zero temperatures are a regular occurrence.

I normally allow my car to idle (warmup) upon a cold start for 2-3 mins for peace of mind and the fact the car is old etc.. would that possibly be enough to warm up the transmission in the process?

 

[Immortality]

Engines warm up quicker than transmissions do, especially if you’re sitting around idling your car to warm it up because it’s snowing outside. Like I said it’s probably more of a potential issue in countries when it gets bollocks freezing than here in Australia.

Engines yes, but the radiator no. Even when you are sitting idling the converter is turning, turning the pump and working the fluid. To do as you suggest you'd need to idle the engine until full operating temp and then some to get heat into the radiator. You don't need high transmission temps ever, trans fluid is very different to engine oil. In the first few minutes of driving after a cold start the engine coolant is not doing anything to heat up the transmission fluid.

Driving is the best way to heat stuff up, when the converter is working it creates heat just like the engine does when it's running. Idling engines for a long time isn't required, most people that do it would do it to warm up the car interior for their own personal comfort and nothing to do with engine/transmission heat.

 

[Immortality]

I normally allow my car to idle (warmup) upon a cold start for 2-3 mins for peace of mind and the fact the car is old etc.. would that possibly be enough to warm up the transmission in the process?

That is fine.

Best rule to remember is don't thrash it until it's warm. No need to warm up the transmission.

 

[Deuce]

I normally allow my car to idle (warmup) upon a cold start for 2-3 mins for peace of mind and the fact the car is old etc.. would that possibly be enough to warm up the transmission in the process?

No.
Transmission takes quite a bit longer than that.

I run transmission cooler out front, and then back through the radiator cooler before heading back to the trans.

Theory is - faster up to temp, twice bringing it down if too high

Example 5.8 stroker, towing a heavy trailer. About an hour from home. Transmission (factory sensor in pan) 77°C

 

[someguy360]

I've always run external coolers on my cars and I've never run them through the radiator, that being said I don't live in a cold climate. I can't speak for areas that get to sub 0 temperatures.

I've always run them direct from the trans to the cooler and bypassed the radiator. I've had to deal with a fleet of BA falcons that milkshaked the transmissions when the radiator split which since has made me not trust radiator coolers (particularly on plastic tanked radiators).

I've had 4l60's run to 500,000km so I'd think if there was a problem doing it this way I'd have noticed it by now. My current one has 300,000km with a 3200RPM stall converter thats under heavy load, still going strong and never exceeds 80c at the track.

I'm about to put one on my VE too which will be a standlone cooler and not in series.

 

[Immortality]

LOL, Fords give internal transmission coolers a bad name (along with alloy heads and head gaskets).

Regular fluid changes is key, don't follow manufacturers recommendations (where have we seen this advice before?).

 

[losh1971]

The wife's 2015 Outlander gets done every 65k. The book says something like 130k. I spoke to Mitsubishi about getting a pan gasket as the ones SCA sells doesn't fit. Turns out Mitsubishi Aust suggest there is no need to drop the pan. Instead you just drain the oil. In the whole time this model trans has been used in the dealers line up Launceston Mitsubishi have never ordered for a customer or replaced a pan gasket or trans filter on one of these. It's as if they almost want the trans to fail. Fortunately the gasket can be reused.

 

[figjam]

LOL, Fords give internal transmission coolers a bad name (along with alloy heads and head gaskets).

Regular fluid changes is key, don't follow manufacturers recommendations (where have we seen this advice before?).

That was the heat exchanger set-up.
Neglected radiators, and their contents, led to corrosion in the heat exchanger, which resulted in a new radiator and a costly rebuilt transmission.

 

[Deuce]

Also, my transmission shifts smoother when it has a little temperature in it too.

 

[losh1971]

Also, my transmission shifts smoother when it has a little temperature in it too.

T56 manual is the same. Mine is fairly notchy until you drive about 5km and get some heat in the oil.