I put a temp sender guage in the OD cut out sender on the trans output line. This was intended to replace the dipstick temp sender. I've been running them both for a while out of curiosity mainly and just to compare.

The dipstick sender measures the tranny temp in the pan at the top of the fluid level. The OD port sender is on the output line to the underbed cooler> engine oil exchange> radiator cooler> tranny.

Once warmed up the line temp lags behind the dipstick by about 20* all the way up to about 180*. Then they mirror each other for awhile. When towing or hauling the output line will then measure higher than the dipstick by about 10* or so.

Seems to me like the temps should be the same or pretty darn close. Both senders are Westach and go to a Westach duel temp guage.

What happens to the fluid between the pan and the output line? Just a pump or does it run through the tranny and thus pick up extra heat?

Any ideas or comments?

 

Fluid circulates throughout the tranny, picking up heat. All your pan fluid temp will tell you is coolest temp of fluid...just before it gets picked up and circulated. Better than no reading at all but nowhere as informative as the temp exiting the tranny after working hard. And no where near 'real time'. JMO

RJ

 

Not quite. The fluid in the cooler circuit has only been through the pump and the pressure regulator valve. Whatever the temp of the fluid in the cooler line, there is hotter fluid in the valve body, converter, and clutches.

 

So then why is the output line cooler than the pan?

And where then is the best place to monitor the hottest fluid?

 

Guess I'm confused, by your wording (and my lack of knowlegde on 1st Gens), on exactly where you located your sensor.
I believe the best loction is the tranny output line, that runs to the trans cooler. According to DTT, this line sees 1 qt of hottest ATF exiting the tranny every 20 sec, at 1100 rpm...... and almost 4 gallons every minute at 2100 rpm.
Try a search. More good info HERE

RJ

 

The line reacts quickest to load.

 

Thats exactly where it is. Just a few inches outside the tranny.
Thanks!