Auto Transmission Temperatures

I've got a Mocal cooler (25 row x 235mm) mounted after the stock cooler (under the nearside headlight).

I'm currently seeing between 60 (evening) and 70deg© (warm day) in the ATF return hose. This is cruising around at legal (sort-of) limits.

What temps / setups do others have? Is this likely to increase dramatically on track days??

All info gratefully recieved.

I've got a Mocal cooler (25 row x 235mm) mounted after the stock cooler (under the nearside headlight).

I'm currently seeing between 60 (evening) and 70deg© (warm day) in the ATF return hose. This is cruising around at legal (sort-of) limits.

What temps / setups do others have? Is this likely to increase dramatically on track days??

 

All info gratefully recieved.

your stock cooler is designed to put heat into the system thats why you are seeing about 70C, mine isn't connected to the cooler so i get about 50C at cruise, to get the best from your mocal you will need to duct it properly or you will (dependent on its position) loose a lot of its effiecency, just putting a cooler in an air flow will not guarantee it works as a lot of the air will just flow round it

So, you're not using the stock cooler in your set-up?

How do you mean designed to put heat into the system? You mean it uses the coolant heat to warm the ATF at cold ambient temps?? Sorry if I'm having a 'thick' moment.

So, you're not using the stock cooler in your set-up?

How do you mean designed to put heat into the system? You mean it uses the coolant heat to warm the ATF at cold ambient temps?? Sorry if I'm having a 'thick' moment.

i have a fluidyne rad which has no trans cooler, yes you are spot on about warming the coolant at low temps

If I remember correctly, the stock auto-box working temp is 80. Ducting, as already pointed out, will make the mocal more efficient. The box won't change into od until a pre set? temperature is reached.

I've got some basic ducting in there, (ally sheet) but i'll seal it better I think.

That's interesting about no o/d until the box is warm.

how much is the max. temp. for the oil of the auto box??

Having searched about I can't find a 'max' temp, but it seems like the ideal temperature is 175 deg F (~80C) to give circa 100,000 mile fluid life.

According to Amsoil "for every increase of 20deg F fluid life is halved". So stick around 175 F and all should be well.

i need the max temp before it can be demaged, for example when im on the racetrack or the autobahn

This might be of interest. Temperatures are degrees F;)

Just thought I'd add some more info -

After 3 consecutive laps of the Ring the temp was 95C.

Cruising back to Calais at 110-120mph it was steady at 70C.

Weather ~ 18C and dry.

This is measured in the return line, post the stock and aftermarket coolers.

interesting im just about to fit the same cooler on mine,just sorting mounting a fan to the cooler at the minute.

have you got a fan on it aswell?

If I remember correctly, the stock auto-box working temp is 80. Ducting, as already pointed out, will make the mocal more efficient. The box won't change into od until a pre set? temperature is reached.

anyone know what temp is required for o/d to start operating?

interesting im just about to fit the same cooler on mine,just sorting mounting a fan to the cooler at the minute.

 

have you got a fan on it aswell?

No fan currently. I've got a track evening at Snett in June, so I'll see how the temps go and make a decision after that.

anyone know what temp is required for o/d to start operating?

I'll try to remember to check this (been meaning to do it for ages).

anyone know what temp is required for o/d to start operating?

cant be sure where it is mate but it is under 50 C as thats when my gauge starts to read, from looking at the gauge i would say 35-40 C but that is a guestimate

Just found this, take a look at page 6 - http://www.autoshop101.com/forms/h16.pdf

Looks like the limit is somewhere between 122 and 162F (50 and 72C), although like Paul I'm sure mine will switch lower than this.

so its worked on the water temp not the oil temp in the box to detemin o/d and lock up

also which is the return line?front or rear one contected to the box

cheers simon

I'm not sure.

Check out the inlet / outlet connections to the cooler in the pic on this thread

http://www.mkivsupra.net/vbb/showthread.php?t=65231&highlight=tranny

and trace them back to the box. Please post your findings for future reference:D

so its worked on the water temp not the oil temp in the box to detemin o/d and lock up

 

also which is the return line?front or rear one contected to the box

 

cheers simon

i would say definately water temp as when i swapped my stock radiator with built in tranny cooler to a fluidyne with external coolers i was surprised to find the box changes up to OD at the exact same spot on the way to work every morning, as for which pipe is which there is a thread on here somewhere that i used that does tell this but i cant find it

Check over the last few cold starts. Mine drops into o/d at an indicated 30C (top hose water temp).

Did an evening at Snetterton last Thursday, weather was dry and sunny.

Trans temp went up to about 93C towards the end of the 20 min sessions. Interstingly, the water temp never rose above about 92 compared to about 100 before the trans cooler was fitted.

So, not putting as much heat into the rad via the trans fluid certainly helps coolant temps.

have you any pics of your new trans cooler fitted please

cheers simon

Pic's of mine in here -

http://www.mkivsupra.net/vbb/showthread.php?t=121357&highlight=COOLER