I just installed a trans temp gauge and after an hour long drive it doesn't read above 120-ish. Does this sound right or is my gauge reading wrong? I put the sensor in the hot line from the back of the trans. At least I think that's the hot line. Thanks in advance for any clarification.

 

Your in the cooled line. The front line is the hot line.

 

O.k. Being in the cooled line then, does this sound normal. The trans cooler is being bypassed right now due to a leak.

 

in the pan i read about 175-200

 

Would I be better off just reinstalling it in the hot line?

 

Most prefer the pan. Depends on what temp you want to monitor. The fluid coming out of the tq converter?(HOT LINE) or the temp of the fluid going into converter.(PAN)
Some guys like to monitor both....(2 Gauges)

 

my pan had a hole already tapped for a probe so that is why i put it there. As long as you know what you are reading and monitor it i can't see how it would make a difference.

 

In the hot line, as close to the trans as possible is the best location. You will actively be monitoring trans fluid temps, as opposed to ambient trans fluid temps in the pan.

The converter output line is the most accurate "real world" temp, and if you see this temp jump, you have a small window of time to get out of the throttle and let the temps cool a bit....by the time a trans pan temp gets into the critical zone, the temps in the converter have more than likely gotten too bad and the damage has started.

 

I like hot line out as well...

http://www.pdrdiesel.com/oldsite/TempChart.htm

 

Dave Goerend says the hot line, thats where I put mine.

 

Pan or hot line. Monitoring your cooled fluid doesn't tell you how hot it actually got, only how much it cooled back down to. Leaves you estimating high temps. Go ahead and move it so you know exactly what the spikes are. Otherwise its like having your pyro at the tailpipe .

 

I was actually wrong, I do have it in the hot line. Unfortunately, I installed it after it goes through the heat exchanger. At least Ive got it before the trans cooler in the front. I am going to leave it and see how it does in the summer.

 

After running for an hour mine will read about 190* (I think, I'll have to look at the guage to be sure. I just remember the needle is about horizontal on the Westach duel guage.) Yours is getting cooled down some so you're still estimating. Not sure how much to add. Kind of like having the pyro post turbo instead of preturbo now (better that the tailpipe though huh?)

A quick easy place is the OD cutout sensor which is right out side the pan.

That "cooler" tube beside the block is actually more like a "warmer". It helps the tranny fluid warm up when first started.

If you decide to leave it where it is you can at least notice spikes or rises and know when to back down. But you still won't know "actual" temps.

 

If you are using an electric sender type of guage you can read both temps with one guage. All you need is a second sender and a SPDT switch. That is how I monitor both my tranny and rear diff.

Unloaded auto trans temps should run between 170 and 190.

Bob

 

Transmission temp should only a concern under long term stress in towing situations. The pan will give you the best average temp over time in a towing situation. The hot line will always be hottest and the return line will always be coolest.

Keep an eye on that hot line sensor when you crest a long hill with a trailer behind you because it will always spike. Personally, I'd rather know whether or not the temp has stabilized at an acceptable level at the end of a long day towing. Then I have a better overall idea of how well my transmission cooling "system" is dissipating heat over an extended period of heavy use.