View Full Version : TR2/3/3A Is this overdrive vent sufficient?

05-24-2018, 08:12 PM
In a post from Randall in response to my question on the overdrive gear & pinion assembly he mentioned that if the overdrive vent was missing or not sufficient, it might cause transmission oil to go into the speedometer cable at the drive end. I dug out some pictures of my overdrive when I "repaired/rebuilt" it. Does the vent stack shown right above the operating valve in this picture provide sufficient venting to the overdrive? Thanks!


05-24-2018, 08:31 PM
Looks fine to me. That's the stock vent, and it's just a big open hole (with a right turn in it).

05-24-2018, 09:15 PM
Any vent is enough, so long as it isn’t clogged. The tranny only takes one “breath” every time it heats up and cools back down. It does not pump air like the engine does.

05-25-2018, 07:53 AM
That's good news! Thank you!