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clinebarger · 09-18-2020, 01:10 AM

4wd 4L80E's don't have a OSS (Output Speed Sensor) Reluctor Wheel on the Output carrier.

I can see using the ISS (Input Speed Sensor) which is actually the Forward Drum Speed with a aftermarket controller & have the false sense of the trans shifting correctly....But it's NOT.

As your NOT using a factory controller (PCM/TCM), They can't definitely say that using the ISS by itself caused a failure.

If the Output shaft was too long & was pushing on the trans geartrain....That can cause several problems in the trans & T-case.

09-18-2020, 01:10 AM	#4
clinebarger Senior Member Join Date: May 2009 Location: Fort Worth, TX Posts: 6,370	Re: 4L80 damaged 4wd 4L80E's don't have a OSS (Output Speed Sensor) Reluctor Wheel on the Output carrier. I can see using the ISS (Input Speed Sensor) which is actually the Forward Drum Speed with a aftermarket controller & have the false sense of the trans shifting correctly....But it's NOT. As your NOT using a factory controller (PCM/TCM), They can't definitely say that using the ISS by itself caused a failure. If the Output shaft was too long & was pushing on the trans geartrain....That can cause several problems in the trans & T-case.