JB.
New member
I bit the bullet and collected, via IR thermometer, the information I had been hoping I'd eventually see posted: Namely, pan temperatures taken from beginning to end of temp check mode. The verdict? When measured on the bottom of the pan (specifically, the rear portion, see pic) there's no temperature lag compared to fluid temps reported by the sensor in temp check mode. Ironically, readings taken elsewhere can show leading temps, but the bottom of the pan is pretty uniform and you can't really go wrong anywhere there. There were lots of measurements taken and I can now do it just by feeling the pan with my hand, but it all just basically confirms the sweet simplicity of <a href="!m132833!http://www.toyota-4runner.org/4th-gen-t4rs/132833-acciently-drained-atf-pan-instead-oil-pan-3.html#post1271592" target="_blank">SkylineGTRracer's method</a> which leaves little room for improvement, but extra context never hurts so I'll write up what I found. The procedures below incorporate the instruction from the official docs about moving the shifter through all positions. I have no idea how important that may or may not be. In any event, the practical joke known as temp check mode is unnecessary.
I like aiming for the lower temperature range for various reasons. The difference between 97 and 115 degrees looks to be about 6oz of fluid or about 1.5% of total fill. Either one of the following methods is easy to do and reliably puts the truck in the lower range of temps with a little margin to spare. After fluid temperature stabilizes, it rises slowly at idle -- about 2/3 degree per minute -- so there's no rushing necessary at all. There was more data collected for the idling version, but the driving version should work just fine. See <a href="!94211!http://www.toyota-4runner.org/4th-gen-t4rs/94211-toyota-fsm-procedure-ws-transmissions.html" target="_blank">this</a> thread for official docs.
(NOTICE: This was done on V8 which has external cooler. Can't imagine that matters much under these conditions, though. I should also mention that the fluid level produced by this procedure matches up with my original factory fill level.)
........Idling version.
With truck completely cold*, ambient temperatures mild, and transmission overfilled:
1. Start truck and slowly move the shifter through all positions before putting it back in park.
2. Leave engine running and let idle for 20 minutes. (Truck temperature gauge should be at operating temp between 10 and 15 minutes)
3. With engine still idling, pull overflow plug (5mm Allen wrench) and let fluid run until less than continuous stream.
........Driving version: Shaves as much as half the time off the above.
With truck cold and transmission overfilled:
1. Drive truck around the block until temperature gauge gets close to its operating temp position and head back to garage.
2. With truck still running, slowly move shifter through all gear positions and then back to park.
3. Let idle 5 more minutes, then pull overflow plug (5mm Allen wrench) and let fluid run until less than continuous stream.
If a level check is desired without overfilling transmission first, the graph should be of some use. Remove the overflow plug and wait to see when fluid starts to flow before replacing the bolt (and gasket). In the lower temperature range, the pan feels like someone's forehead with a fever. At 115 degrees, it's still easy to press a hand against the bottom of the pan and hold it there. At 125 degrees, it becomes obvious that it will soon become hard to leave the hand in place, if it's not already. At 135 degrees, the hand can be pressed briefly but I doubt many can leave it there.
Pan temperature rise for the idle test. Truck was *15hrs cold and garage temp was the same as pan temp. I presume the steep rise in the first 5 min is from residual system heat circulating through the pan.
Temperature reference spot in white. Numbers are approximate.
I like aiming for the lower temperature range for various reasons. The difference between 97 and 115 degrees looks to be about 6oz of fluid or about 1.5% of total fill. Either one of the following methods is easy to do and reliably puts the truck in the lower range of temps with a little margin to spare. After fluid temperature stabilizes, it rises slowly at idle -- about 2/3 degree per minute -- so there's no rushing necessary at all. There was more data collected for the idling version, but the driving version should work just fine. See <a href="!94211!http://www.toyota-4runner.org/4th-gen-t4rs/94211-toyota-fsm-procedure-ws-transmissions.html" target="_blank">this</a> thread for official docs.
(NOTICE: This was done on V8 which has external cooler. Can't imagine that matters much under these conditions, though. I should also mention that the fluid level produced by this procedure matches up with my original factory fill level.)
........Idling version.
With truck completely cold*, ambient temperatures mild, and transmission overfilled:
1. Start truck and slowly move the shifter through all positions before putting it back in park.
2. Leave engine running and let idle for 20 minutes. (Truck temperature gauge should be at operating temp between 10 and 15 minutes)
3. With engine still idling, pull overflow plug (5mm Allen wrench) and let fluid run until less than continuous stream.
........Driving version: Shaves as much as half the time off the above.
With truck cold and transmission overfilled:
1. Drive truck around the block until temperature gauge gets close to its operating temp position and head back to garage.
2. With truck still running, slowly move shifter through all gear positions and then back to park.
3. Let idle 5 more minutes, then pull overflow plug (5mm Allen wrench) and let fluid run until less than continuous stream.
If a level check is desired without overfilling transmission first, the graph should be of some use. Remove the overflow plug and wait to see when fluid starts to flow before replacing the bolt (and gasket). In the lower temperature range, the pan feels like someone's forehead with a fever. At 115 degrees, it's still easy to press a hand against the bottom of the pan and hold it there. At 125 degrees, it becomes obvious that it will soon become hard to leave the hand in place, if it's not already. At 135 degrees, the hand can be pressed briefly but I doubt many can leave it there.
Pan temperature rise for the idle test. Truck was *15hrs cold and garage temp was the same as pan temp. I presume the steep rise in the first 5 min is from residual system heat circulating through the pan.
Temperature reference spot in white. Numbers are approximate.
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