Re: 4R100 O/D Light blinking and slipping out of Overdrive
There are two scenarios I can come up with where it would shift to neutral, or at least appear to shift to neutral.
One is a bit farfetched but within the realm of possibility. That would be the TRS (Transmission Range Sensor) failing. The problem with this is that it will shift to first gear as it is failing, so that would have to happen when the trans shifts 3-4.
The more likely scenario is that the overdrive clutch snap ring has come out of it's groove and the overdrive clutch has fallen apart.
Former Ford Automatic Transmission Engineer
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