Tap size question

[tracerbob]

I need to chase the threads to remove a burr or two on the filler spout on a 45 3 speed tranny but it appears to be a non standard thread size. Any ideas what it might be? My thread gauge only goes to 13 tpi and it appears to be courser than that.

Thanks
Robert

[BigLakeBob]

11/16-11. That's what I measure and Colony catalog says the same. Some taps are listed in MSC doing a search, one as cheap as $14.

[len dowe]

That's good to know Bob. Thank you.

[tracerbob]

Wow, that is an odd ball thread size. Thanks for the reply Bob.