Transmission fluid temperature D4D

[Tezza222z Junior Member Find all posts View Profile Close Tezza222z]

What temperature is the warning light set to come on at with the auto trans. Now that the ScanGuage can read the TFT it is only useful if we know the acceptable operating range. Anybody know????
Thanks
Tezza

[Tezza222z Junior Member Find all posts View Profile Close Tezza222z]

To answer my own question after some research; auto trans fluid should be at around the 80 deg C mark for normal operation. It needs to be over 70 deg for efficient operation and anything over 100 deg is a problem that will lead to seriously reduced auto life. Apparently even short spells over the normal range does damage to seals and to the oil itself. Now I need a big hill to see how hot mine gets.

[Rusty62 Advanced Member Find all posts View Profile Close Rusty62]

Just bought a new scangauge for the auto temp. Normally runs at between 80 and 95 deg without the trailer. Towing camper off-road last week saw temperatures of 137 deg. This was climbing from 135 meters above sea level to 1100 meters in the national parks near Armidale. Interesting the auto will heat up when going on long downhills as well. May look at the lockup over ride for the torque converter as this would be the the cause of the heat. When the torque converter is locked on the highway 100 km/h towing temps would drop back to 90 degs or so. Cooler will be installed when funds allow as well. The car is now 165000 old and has seen many km as a tow car. Roo changed the oil recently and to date no ill effects from towing.

[mjrandom Out of control poster! Find all posts View Profile Close mjrandom]

Rusty what was the oil like?

[Heath74 Senior Member Find all posts View Profile Close Heath74]

Mines a 120, but the point stands, when towing, they like to be back in 4th especially on the hills. Once the torque converter clicks in the trans temp spikes. I'd be interested to know how much of a difference the cooler makes. Just towed 1300km today, and really noticed the temps spiking on climbs.

[Anth120playdo Banned Find all posts View Profile Close Anth120playdo]

Heat is what will kill your transmission.
Add a Towbar & add a cooler.
These transmissions are very good but best to keep it cool.
Under 100 would be ideal.
Oil change every 12 months or 50k.

Id like to know what temp the light goes on, I'd imagine somewhere over 100.

[Prone Member Find all posts View Profile Close Prone]

Check out this link. See post 32

http://www.pradopoint.com/showthread...0-series/page3

It will give you the code to get x-gauge working for the other transmission temp sensor. There are 2 temp sensors in the transmission, the standard scangauge shows the torque converter temp (TCT) and displays it as TFT, the x-gauge code will give you the temp in the main part of the transmission. It tends to be lower and more stable. The torque converter temp will rise and fall fairly quickly with load and converter lock-up.

Fitting the oil cooler dropped the fluid temp on mine about 20 degrees. There is a thread that covers this fairly well also.

http://www.pradopoint.com/showthread...cooler-fitment

With the oil cooler the normal range for mine is about 65-75 for the x-gauge and same for the scangauge TFT reading when the converter is locked. When towing, steep hills, high speeds, hot weather etc, I have still seen 120 on the TFT reading but the x-gauge has not gone above 90. Much better than without the cooler.

I believe the temp warning comes on about 150C.

Fit a cooler if towing.

Cheers
Prone

[Rusty62 Advanced Member Find all posts View Profile Close Rusty62]

Oil was dis colored but not as bad as soon I have seen. Interesting reading the post on the second x gauge sensor for the main box. Will look at that one when I get for the trip home. Experimented towing this week and as others have said when climbing and the auto unlocks, bump to 4 th gear and the torque converter will re lock. Revs unlocked in 5 th are almost the same as locked in 4 th but the temperature, at least in the torque converter stall below 100. Have just entered the second temperature x gauge and will look at on return trip from Rocky to Brisvegas on Saturday.

[ptnlinda Member Find all posts View Profile Close ptnlinda]

Took the new Camper Trailer for a run on the weekend so thought I would experiment with what gear I would run in. The tow vehicle is a diesel GXL with Auto and accessory Auto Transmission oil cooler fitted. We only went 100k's down the road to Adelaide River but the observations were quite enlightening. On the trip down on Saturday ambient temperature was 33c and the Auto was in "D". We sat on 100kph. According to the scan gauge the Auto Box ran at 86c but when the auto changed out of overdrive the temperature at the torque converter got to 105c. I monitor both the auto box and torque converter oil temperatures on the scan gauge. As soon as the auto got back into Overdrive the temp came back to that of the oil in the auto box. This happened the whole way to Adelaide River.
On Sunday coming home the ambient temperature was 37c but this time I left the transmission in S4 as recommended in Mr Toyota's manual. What a difference. The torque converter temp only got to 105c when taking off and getting up to 4th gear and the 100klm I traveled at. The rest of the trip the temperature for both the oil in the auto box and at the torque converter stayed at 77c. Cooler than the trip down even though the ambient temperature was much hotter. From this I have learn't Mr Toyota knows what he is talking about and will in future be towing in S4 as recommended.

[Heath74 Senior Member Find all posts View Profile Close Heath74]

Thanks for the link prone, that code works for the 120 as well

[Foxy48 Member Find all posts View Profile Close Foxy48]

Roo, Mate, your so right about that front plug on the front diff . I tried to do it diy but before I actually could stuff it up I stopped as I realized even with the correct tools (Allen Key) I could not budge it .I have left it for my dealer to do it at the next service cos then it won't be my fault .I did the rear diff and I was surprised to see how dirty it was and I changed the transfer case as well . With the Auto trans I have fitted a oil cooler which to me is a must when towing which I do, I have a temp gauge on the return pipe and the oil is always usually at about 140 F- 160F when under heavy load (Towing) but what worried me more was the temp of the engine oil which at times hit 200 - 220 degrees F. On a recent trip it hit that temp 3 times so as soon as I got back home I dropped that oil and filter and added new .Certainly after a long trip the engine sure runs better after a good workout .So I really am considering adding a engine oil cooler as well .hope this may help Cheers Foxy