Practically Classics Forum

As everybody keeps saying cooling is good!

Then here is a question, what about heating, and the correct/best
operating temperature for the oils which are used in the various
different systems which people keep forgetting.

Consider this in the Chrysler Neon radiator there is cooling for the
automatic transmission. But how many realise this also works in
reverse for those cold mornings, as the car is sat ticking over and
warming it's self and demisting the inside. The heat is helping to
get the transmission fluid to usable state quicker.

And thus less stress and wear on the Transmission than on a car
which has a separate transmission oil cooler.

What is it this cooler in the radiator? A coil of pipe just in one of the
tanks of the radiator, not even half the length of that tank.

If you take this to it's logical con conclusion for smaller engined
vehicles or those that are in colder climates, having not only the
transmission cooled inside the tank of radiator but also one or the
power steering makes common sense idea for older cars(if possible).

So how many people have realised this?
And how many have actually done something to help their cherished
old car by doing something like this?

Just a thought, to get you thinking

Mitsuru wrote: Consider this in the Chrysler Neon radiator there is cooling for the
automatic transmission. But how many realise this also works in
reverse for those cold mornings, as the car is sat ticking over and
warming it's self and demisting the inside. The heat is helping to
get the transmission fluid to usable state quicker.

But it doesn't work like that. The coolant takes longer to warm up than the transmission fluid does. Most transmissions have a thermostat in there that prevents any flow going to the radiator until the transmission is fully up to temperature anyway.. In practice the coolant never does warm the oil, it's the other way around.

Mitsuru,

a) Some of what you have written in a style that would indicate that you consider it "fact" is actually incorrect, as Richard Moss points out.

b) What makes you think that the rest of us are ignorant of these principles? You need to be aware that many members on this forum know a great deal more than you do, and some of us find this rather insulting.

Well I never did! This revelation should save me a fortune as I'll no longer need to buy Fisherman's Friends to crumble into the expansion tank on those chilly Winter's Mornings....

In sufficiently cold climates, engine preheaters are fitted as standard...

Transmission coolers in the coolant radiators are just a cheap option for the manufaturers, because they don't care about the problems when the pipe in the rad cracks, and fills the cooling system with ATF, and the transmission with coolant. Good for the trade, but not so good for the owners...

Having them 2 in 1 saves a bit of space under the bonnet too which is at a premium in modern cars.

Nope i definitely haven't forgotten that coolant is used to maintain the correct engine temperature and i also haven't forgotten that oil is used to separate a static surface from a running surface.

But thanks anyway.




Would of been better posted as a query/question rather than a revelation.

Out here in the desert there is a slightly different issue - in off-road use the transmission oil can overheat the engine coolant. The transmission fluid on my Gulf-spec Jeep Grand Cherokee is cooled by the main radiator first and then goes through an air-cooled auxilliary cooler before going back to the transmission. Quite a few owners will bypass the radiator and fit an oversized auxilliary cooler instead (often with an electric fan on it) therefore avoiding pumping excess heat into the engine coolant. I'll probably do this soon, working on the principle that air at 35-40C is likely to be a better coolant than ater at 100-110C.

The power steering fluid also has a small air cooled auxilliary cooler on it - something I've never seen before.

The chrysler neon is not the pinnacle of automotive engineering, it sounds like a rubbish alternative to a seperate oil cooler for the reasons said above and that if the engine overheats your going to heat up the auto box too and damage that too. That way must limit the size of the cooler too?