Topic: Speedometer cable leaking transmission fluid

[MattDoscher]

On my wife's '65 Comet the speedometer cable will allow transmission fluid to leak out from around the plastic cable housing where it transitions to the metal part going into the C4 transmission.  It's not coming from the O ring it's somehow leaking through the inside of the cable/driven gear and leaking out from where the outside plastic housing of the cable transitions to the metal part of the cable.  It seems to only start leaking when the car has been sitting for a few days.  Is there some sort of seal inside the cable behind the driven gear?  Or do I just need to get a new speedometer cable assembly?  If the O ring was bad the leak would come from further up towards the transmission.

thanks,
Matt

[KK2558GO]

First of all make sure the vent is not plugged. The riffling of the inner cable should send the fluid back into the trans housing when driving (forward). I have seen replacement inner cables that were wound incorrectly and would actually pump fluid all the way up to the speedo instrument.   Under normal conditions, the trans fluid never get to the level of the cable and inner driven gear when the car is parked even for long periods of time.  To answer your question about an inner seal, no, there is no other seal other than the o-ring .  You could try some sort of sealant to help the integrity of the steel tubing to plastic cable  connection.

[MattDoscher]

Thanks for the advice.  I'll have to check the condition of the vent.

Matt