Lifetime Premium Member
Join Date: Jun 2018
Location: Central CA coast
Help me determine trans. cooler fitting.
I managed to twist one of the cooler line fittings in half on my transmission and can’t figure out what size it is.
TH-350. Not original to my car so I’m not certain what year it was manufactured or what it was first installed in. It does have the standard Chevrolet bellhousing. The cooler lines themselves are 5/16” with flare fittings.
The fittings have straight threads and 18 threads per inch with a flat sealing washer that mates against the case. The threaded portion looks to be about 1/2” in diameter, but a 1/2” wrench will not fit over the threads. A 9/16” wrench just rattles around on it.
If I can identify the threads that go into the transmission case I will likely just replace these fittings with a -6 AN adapter and graft new -6 lines onto my 5/16” cooler lines.