Any chance of pictures of the connector and measurements with a caliper? Particularly the length of the portion that slots into the other connector. I have one of my old hubs w/factory sensor lying around *somewhere*, could compare it but may take me a while to FIND it.
I have replaced both my '98's front hubs, but did not use Motorcraft, one was Timken and the other more recently.. hmm... Centric's upper line, 402.65010 because I happened upon NOS $48 delivered on ebay, otherwise would have just gotten another Timken. Ironically the Centric did have Timken bearings. Both plugged in fine.
Old sensors, depends I suppose but the first of mine fractured apart trying to remove from the hub, rust had seized it in and there's no forcing (nor heating with a torch) thin walled plastic like found on those ABS sensors. In retrospect, a better attack at getting a rust seized sensor out of a hub you're replacing anyway, might be repeated applications of acid to break down the rust, without harming the plastic, but it seemed a pretty tight fit, trying to keep applying acid with just a hope it'll work, could get tedious.
Here's a crazy question. Does the connector have a rubber seal on it? Is it possible that when you unplugged the old one, the seal came off and stayed in the mating connector? Seems unlikely since it's presumably happening to both of them, but stranger things have happened.
