Gevo

Research is telling me that the condition for the A/T light to come on is 300 or 305 degrees F. Also, that once the oil has reached this temperature, and given that the dipstick doesn't show particulates in the oil, to change the oil since it is the heat that breaks it down.

First question is, does anyone know any differently than the above mentioned items?

Shall I change the oil by a simple drain through the drain plug and refill? The current oil is only 5000 miles old after rebuild.

Also, what is the condition of the A/T Temp light to go OFF. What happened for me was a long hill climb at 60 mph in 3rd, and I wanted to test the abilities so with the ECT button activated, the little additional throttle put the tranny in 2nd gear, at 5000 rpm. I kept it here for about 30 seconds, then let her back in to 3rd. Maybe another minute or so and the light came on. At this point I was at the top of the hill and let off to an easy powered drive at 2000 rpm. The light didn't go off. I pulled over, maybe 5 minutes to check the oil level etc (was all good), started her up and no light. SO, what is the condition for the light to go off? Does a reset of the ECU (ignition ON/Off) turn it off even if the temp is still high? Or does the ignition on/off cycle not matter and it was coincidence? If it goes on at 300 degrees, does it go off at 299? Or, does it stay on for a length of time... etc.. I read through the autoshop 101 manual but it didn't really answer this question.
http://www.autoshop101.com/techartic...ticles.html#AT


Thanks!

4mydogs

So the light is staying on? Wish I could answer your question. The one time that mine came on, I pulled over and put the trans in park and let the engine idle (like the manual says to do). After a few minutes (4-5) the light went off. When I got home (was on a trip), I had a transmission flush done. I also installed a transmission temp gauge so that I could tell exactly what was happening and when. Interesting to watch the temp climb in stop and go traffic, then settle back down at highway cruising speed. I've also noticed that turning the OD off when doing long climbs makes all the difference in the world.

Gevo

The light didn't stay on after I turned the car off for a couple minutes, then back on. This is after I let her cruise at low rpms with the light on, to cool it down. So, from what I am understanding with your experience, the light should go off when the temp drops back down? I have been meaning to install a tranny temp gauge myself, but haven't found one that I like. What did you use? How big is the gauge? I have purchased a tranny oil cooler a while ago, but can't fit it anywhere to mount.

4mydogs

Yes, that was my experience. And from watching the gauge, it seems that when the temp is climbing, the two ways to get it back down are to either let it idle in Park or to cruise at speeds 45-50mph and up where the transmission is "locked" in high gear.

I bought one from Auto Meter, similar to this one
http://www.autometer.com/cat_gaugede...id=2799&sid=15
and mounted it on a pedestal (also from AutoMeter) next to the shifter. Worked great.

wyoming9

iTrader: (1)

I could be wrong but looking at my 88EWD that is a thermister so when the temperature drops back to the lower temperature the light should go off if the whole system is working like it should.

even if you cycle the ignition switch if the ECT sees the signal to turn the light on it will.

Get your transmission cooler mounted and a gauge installed

Gevo

Thanks for the post. I did a bit of research and eventually also purchased the same auto meter gauge. I looked at some places to mount it, i'm going to try above the dome light dimmer switch on the dash. If that doesn't work, I have to spend more money and get a mount kit and mount it ahead of the shifters on the 'floor'.

Wyoming, this saturday I'm doing a full tranny fluid dump and refill, new filter, new kickdown cable and finally install my B&M cooler. I haven't figured where yet :/

Gevo

Question about the temperature sender unit location. I read and read, but there seem to be people installing it all over the place and so follow the advice.

I was thinking I should mount it in the line going TO the cooler from the tranny, this way I can get a reading of the highest temp that the tranny sees. But I am seeing lot of people installing it on the return line from the cooler, and a B&M gauge manual said the same. Which is correct and why?

Thanks!

rworegon

Mine is mounted as you state here. Seems pointless to mount it in the pan or after the cooler since it's heat that damages a tranny, therefore, I want to know the highest temp.

4mydogs

That's what I did. It seems pointless to measure the temp of the fluid after it's been cooled.

Gevo

Thanks for confirming guys! I'll work on the cooler install this friday. If anyone has mounted a B&M cooler to a 1991 3vze 4runner with AC and 4x4, let me know. Cause, I can't fit it in the grille area!