Just external trans cooler

[mpack88]

I have two vehicles that have the radiator cooler bypassed and they are only using the external trans cooler. I have not verified the temperatures as I'm not sure where to get them. I'm assuming the inlet line? One of these cars is a 91 Ford Taurus which is infamous with tranny issues. Its factory lines cracked and I added just the external. Seems to do ok. The other is a 75 ltd with a c6. Pretty good trans and dosnt seem to mind just using the cooler. What's y'alls opinions on just using external cooler? Should I use both? Both are aftermarket units.

 

[ABN_CBT_ENGR]

If you have the flow/surface area to remove heat to the acceptable level- they are fine

If not- they need additional cooling

 

[E150GT]

I'm interested to see what others say. I myself had a van with a C6 that i struck a deer with and knocked out the front mounted trans cooler. I bypassed it in the side of the road and never fixed it. The transmission died maybe a year later. I do believe that had something to do with it but I could be wrong.

 

[mpack88]

Originally Posted by ABN_CBT_ENGR
If you have the flow/surface area to remove heat to the acceptable level- they are fine

If not- they need additional cooling


But where would be the best place to get a tempurature reading?

 

[FlyNavyP3]

The best place is pan temp, the transmission outlet to the cooler (pre-cooler) will be hotter than bulk pan temps. Likewise, cooler return would be cooler than pan temps. Pan temp is the most accurate representation of the fluid temp being sent to clutches, seals, converter, bearings.

 

[ABN_CBT_ENGR]

Originally Posted by mpack88


But where would be the best place to get a tempurature reading?


That depends on the answer to this question for any type of heat exchange design- especially a kidney loop

Which matters most to you?

The load on the machine which is generating the heat- they sensor would be located at the last point in the work cycle to tell you if a mechanical issue exists. (Usually on the discharge of the system pump) Theoretically this would be the hottest.

Post after cooler- this will tell you the percent heat removal and in a car with those short runts a good indicator of true heat exchange.

Sump- this will tell the static temperature of the oil in general and indicate if the oil going in has too much heat thus affecting system exchange and it tells you what is about to go through the transmission

Personally, if I know I am going to be running heavily loaded at all times, I would want all 3 to give me a full system status indication.

If not, at least on both sides of the heat exchange circuit to roughly estimate the above.

 

[mpack88]

Well sump temp is where I'll look. I'm assuming trans temp is about the same as engine oil temps. 190° to 220°?

 

[ABN_CBT_ENGR]

Originally Posted by mpack88
Well sump temp is where I'll look. I'm assuming trans temp is about the same as engine oil temps. 190° to 220°?


I would want mine around 170° under load if I were adding additional exchange ability