RngTrtl

Dear All (1985, USA, 5.0L,32V,Automatic)

I have just gotten a tranny temp gauge (Autometer Phantom series, electric) and am curious as to where the best place to mount the sending unit is. I am guessing that at the tranny would be best, but exactly where to mount it is my biggest question.
Thanks in advance to all for the help.

blown 87

AutoMeter used to make a block that you put inline on the cooler lines. I have one on my 70 SS 454 Chevelle, not sure what sizes they have, I think mine was a AN-10.

Bill Ball

Would the pan be a bad location for some reason?

RngTrtl

I was thinking the same as you bill about putting it in the pan. I am just not sure where to get the most accurate (or rather useful) reading from in regards to the tranny temperature. Like would the temp of the feed line to the cooler be too hot, and vice versa would the return line be too cool...I am thinking that I should put it in the pan as well to give a good overall reading of the tranny temperature. Where are the temp senders for race/performance applications mounted?

SharkSkin

I'd say if you're running it hard enough to care about trans temp you should put the probe in the line to the cooler. The line to the cooler would give you a better read on how much heat the trans is trying to shed, and should give you quicker warning if something is starting to overheat. Putting the probe in the pan will tend to mask an overheating transmission longer because you're getting cooled ATF poured in there constantly. Since ATF begins to break down quickly over about 220F it might be a good idea to check it at the hottest point in the system.

BrianG

It used to be that Auto-box temp sensor kits provided a selection of bushings so that you could fit the probe to any transmisssion pan drain plug hole. That might be problematic if the pan is the lowest point on the car, or if the pan didn't have a drain plug.

In any case, the pan is the appropriate place for the probe since this is the oil temp that the transmission sees, for the most part. The oil pump pushes oil through the torque convertor last, and then out to the cooler. Of course the torque convertor does most of the oil heating. There is little value in seeing the temp of the oil immediately after heating because nothing else in the transmission will ever see that temperature, and it WILL scare you if you see it!.

Dave is right, if you want to monitor max-oil-temp, but it's usually transmission operating temp that one is interested in.

RngTrtl

I really appreciate all the advice on this. Brian pretty has my application nailed down. So I am gonna mount it in the tranny pan, now I need to get appropriate safe and unsafe temperature ranges that I should or shouldnt be operating in. Any ideas?

Jim bailey - 928 International

The heat exchanger (trans fluid cooler) in the radiator is on the hot side of the radiator so it sees the coolant after it leaves the engine and BEFORE the radiator core has cooled it down the the temperature that the thermostat is trying to maintain on the cooled coolant entering the engine. So 85 C is the normal thermostat and the temperature on the passenger right side of the radiator is significantly higher. So the question of How hot is too Hot ?? The 87 S-4 has an overload protection switch part # 002 545 451 4 which tells the fan speed controller it is time to cool the radiator.