Weird Occurrence When Draining and Filling Transmission Fluid
#2
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The other day a friend and I did a transmission drain and fill for my 2016 IS350 (AA81E). We followed the proper instructions and put the car into the transmission drain and fill mode whilst maintaining the proper transmission fluid temperature 97F-126F. The issue is when we opened the overflow plug nothing came out for a good 30 seconds, afterward about a good 1/3 quarter of fluid came out. Now the car has a somewhat rough shift from 2-3 with low throttle application, almost as if it is delaying the gear shift.
This might be one of those where you need to go and re-check the overflow plug when it's at operating temp again. These transmissions are very sensitive to fluid levels.
#3
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You said “afterward”. After what? If no ATF fluid comes out, you don't wait until ATF comes out. You shut it off, add about half a quart, then check the level again during the prescribed temp range. Repeat if no ATF comes out. It appears your ATF level is currently low.
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jmatc (09-30-22)
#7
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Sounds like you were underfilled to start and then let more out. If you are within temp range and nothing comes out initially then that's a sign that you are already underfilled.
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#8
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ATF expands as it warms up. If a little low, ATF will eventually come out. The lower you are, the longer it will take for ATF to trickle out.
Your procedure is off in that when you remove the drain bolt, you don't wait for ATF to come out if none comes out right away. ATF should pour out when you remove the bolt during the prescribed temp range. If none cones out immediately, you are low in ATF. Put the bolt back in and add half a quart of ATF, then check the level again, during the prescribed temp range. If none comes out, repeat. If ATF comes out, let it drain until it starts to trickle out. This should be within 15 seconds. You don't want to keep the drain hole open past the temp range because you wont know if ATF is draining because it is too full, or because the ATF has expanded due to the higher temps.
Your procedure is off in that when you remove the drain bolt, you don't wait for ATF to come out if none comes out right away. ATF should pour out when you remove the bolt during the prescribed temp range. If none cones out immediately, you are low in ATF. Put the bolt back in and add half a quart of ATF, then check the level again, during the prescribed temp range. If none comes out, repeat. If ATF comes out, let it drain until it starts to trickle out. This should be within 15 seconds. You don't want to keep the drain hole open past the temp range because you wont know if ATF is draining because it is too full, or because the ATF has expanded due to the higher temps.
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kj07xk (07-30-22)
#10
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the issue is when we opened the overflow plug nothing came out for a good 30 second
Was the engine shut off, when you were checking the level, or was it on?
This is how I did mine:
....
Overfill the tranny (by a good quart or so).
Get to OP temp.
Open the plug.
Wait until the trickle starts (as opposed to a good solid fluid flow)
Close it without waiting for the trickle to completely stop.
In your case, it was def telling you it was underfilled, and then you waited (for some reason) another 1/2 minutes, until it lost even more fluid.
This is not how it was supposed to be done. As a result, your already underfilled tranny lost even more fluid.
You def need to OVERFILL it first, and then let it drain to get to the correct level. Also, be on the safe side and check on the lower level of temperature range, rather than approaching its upper level.
#11
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You said “afterward”. After what? If no ATF fluid comes out, you don't wait until ATF comes out. You shut it off, add about half a quart, then check the level again during the prescribed temp range. Repeat if no ATF comes out. It appears your ATF level is currently low.
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