Hey I was just offered a free little tranny cooler. After talking to my dad, he said it would keep the tranny too cold in the winter time.

The car is an 82 TA, LG4, 200C 3 speed with 3.73 gears. You can feel the heat when you put your hand on the center console.

I live in wisconsin, and the coldest it would get would be 0 degrees. The warmest it gets in the summer is in the 90s.

 

It won't keep it too cool... Besides, too cool is much better than too hot. If you retain the radiator trans cooler, thats the best of both worlds (radiator cooler and aux trans cooler).

 

Zero Farenheit? Pfft.. that's not even cold yet.

If you put the cooler inline with the factory cooler then it should be fine.

 

Yup, I'm talking in degrees Fahrenheit. I guess I'll pick it up sometime soon.

 

Actually it can keep the fluid to cool in winter. Tranny fluid works best at a certain temp. Lowering that temp can cause more harm then good. GM recently started putting thermostats on coolers.How big is the cooler?? If its just a small one then I wouldnt worry about it.

 

happened to run across this post and thought i would toss in my 2 cents. as long as you hook the cooler on the line going to the radiator and not the return line you have no worries. it will cool the fluid before the radiator gets it in the summer, and in the winter the radiator heats the tranny fluid as soon as the radiator gets warm so with the cooler on the input (radiator) side even if the aux cooler gets it too cool the radiator will warm it right back up for you before it hits the trans.

 

I hooked my transmission up to the A/C condenser only, (no radiator) since the A/C didn't work and I don't drive my car in the winter.

This is a topic of much debate and many differen't opinions.

IMO I do not believe that you can run a hydraulic system "too cold". I am a maintenence tech at a factory and cooler is better in our hydraulic systems. And what is an auto trans? A hydraulic system. Yes, tranny fluid is differen't from regular 10W hydraulic fluid, but its still a hydraulic fluid.

I took my transmission over to my Dad's place and we rebuilt it there. He rebuilt truck and bus allison autos for many years and it is also his opinion that you can't run a transmission too cold.

IMO GM probably wants tranny temps up for efficiency and consistancy reasons. Plus it will heat the fluid up faster to give you proper operation quicker in cold weather.

I will admit that an auto will be sluggish when really cold. But it will warm up. Think about this, On a 85 degree day your car is cold, you havn't driven it all day, you get in, start it up, drop it into gear and mash the throttle to the floor (not that you want to do this to a cold engine). The tranny works fine right? Well I am pretty sure that in the dead of winter, your tranny will operate over 100 degrees once it warms up.

IMO no matter how cold it gets with a regular tranny cooler and bypassing the radiator connections, you shouldn't have any problems.

EDIT: I am not promoting the bypassing of the radiator conections for everyday use. You may want to keep that hooked up for daily winter driving to warm the tranny up faster. But if that doesn't bother you, then try it without the radiator. Its not like you can't hook it back up.

 

So, going by this last post it is better to route the cooler lines through the internal cooler in the rad. then through the external cooler (in my case a large Perma Cool cooler), rather than the other way around?

I live in Houston--very rare that it gets below freezing.

Where is the best place to measure the tranny fluid temp? (I have a Auto Meter sport comp tranny temp gauge that I have not installed yet)

I know the cooler the better, but what temp is good/bad?

If memory serves (usually doesn't!) the bottom cooling line on the tranny is the "send" line with the top being the return line?

Thanks,
Craig

 

Yes

 

hey Zap, on your question, i have a 8 pass tranny cooler about 1/3 the size of the condenser on my car & i don't run through the radiator as running it through 200+ degree water only helps to
heat it up more.
i would love to keep my tranny under 100 degrees if it were possible.
probably the best place for the gage would be through the side of the pan where it won't interfere with anything.

 

I have read a few articles on trans coolers, and ran a few myself. I have always ran the cooler between the return line from radiator and trans. do i have any "real world" tech to say its better ran this way? nope. but I will try to lay out my thinking for you after reading these articles. with the cooler inline before the radiator your cooling your fluid and then the radiator may be heating it back up some depending on your coolant temp vs trans temp. If you send it through the radiator first your going to slow down the total cooling effect of the radiator a little it since the fluid is max heat when it hits the radiator but the radiator was designed for this. then as the fluid leaves the radiator the aux cooler will cool it more. thats the summer effect. and would be the "best" trans cooling. In the winter if your area gets very cold your going to keep the fluid from reaching its "operating temp" alot longer with the cooler after the radiator vs before the radiator. Its really a personal preference but we are trying to cool down the tranny and both ways will cool it, the question comes in the winter, are you cooling the fluid too much for the first 25-30 miles of operating with the cooler after the radiator while the trans warms up. I am NOT a tranny guy , hell i am going to attempt my first 700r4 rebuild this winter and will need alot of help from you all i am sure. so i dont mean to bump any heads here but this was my 2 cents worth.

I would love to hear some thoughts on this from probuilt trannys as i am sure he has a ton more exp than i do on this subject.

 

Do U want to measure the tranny fluid temp before it is cooled--like we do water--or after it is cooled?

Measuring it from the pan would be after--correct?

Does 100% of the fluid go through the cooling lines or just a portion with the rest going back directly in the pan?

 

Hot fluid is picked up in the pan and is cooled before being routed to the converter and lubrication circuits.

 

as Apeiron said, what comes from the cooler is for the converter & to lube & cool the trans, the parts that need high pressure such as the apply pistons & accumulators comes right from the pump.
measuring it in the pan would be before cooling it, thats why a finned aluminum pan really helps to keep the tranny cool.

 

Incidentally, one of the reasons TCC operation is important to the longetivity is that maximum flow through the cooler occurs when the TCC is locked up.