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NB 6-speed AZ6 Neutral Switch

Old 05-20-2019, 11:10 AM
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Default NB 6-speed AZ6 Neutral Switch

I rebuilt my AZ6 trans over the winter and have run into a snag during the test drive.
I had to replace the neutral switch because during assembly I torqued it to the specified 22-28 ft-lbs, which seemed ridiculously high and, of course, sheared the sensor in half.
I installed a new sensor and used a new OEM crush washer for the reverse switch. Looking at the schematic there is no mention of a washer for the neutral switch, which is identical to the reverse switch other than the wiring connector. There is also no mention of thread sealant in the repair manual.

During the test drive I had a wonky idle and have a P0705 mil code for the neutral switch. I was messing around with a DVM and the contacts are not opening up in the switch with the trans in-gear if I have a crush washer. I can't find any disassembly pictures of the stock sensor, since it was basically the most trivial part of the job.

Does anyone know how this thing is supposed to seal to the trans?

Other than that the trans rebuild is working beautifully. At least I didn't screw up something major...
Thanks for the help!

Last edited by engineered2win; 05-20-2019 at 11:48 AM.
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Old 05-21-2019, 08:09 PM
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I replaced one that was leaking fluid through the switch. I recall just putting Permatex #2 on it, no issues since.
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Old 05-26-2019, 02:32 AM
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The neutral switch is high enough that it doesn't really need sealant. Reverse switch is submerged, thus the washer. Lack of sealant may be the reason for the high torque value; just enough plastic deformation to seal it up.
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Old 05-28-2019, 11:32 AM
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Torquing the neutral switch to spec cost me two switch. IIRC on the 3rd we put a crush washer and just tightened it until we we comfortable. This is on a NA8 with an aftermarket ECU, so I'm not sure how this would effect a NB.
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Old 05-29-2019, 07:46 PM
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I didn't like the idea of an unsealed hole on my trans. I went to Autozone and found a copper crush washer in their misc package that was 0.020" thinner than the OE washer for the reverse gear sensor (0.040 vs 0.060"). It was just thin enough to depress the switch in all gears. I had to buy a sensor socket set from Horrible Freight to get the 27mm socket to torque the sensor. This time I only tightened it to 15ft-lbs, which caused the sensor to not break in half. I was at Mid Ohio over the weekend with NASA and everything worked as it should; no leak and no wonky idle. Shifts damn quick now with the Supermiata twin disk race clutch.
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