Greetings all.

This is in regards to my '66 130 with a b-20 and M41 transmission.

Most of the time the OD works as it should. In 4th gear, flick the switch, and a half second later, the car jolts into OD just like they all do.

Here's the weird thing though:

On longer trips (especially on hot days), the OD won't disengage when I hit the switch. The relay setup isn't failing, voltage is removed from the solenoid. (I have verified this by pulling the relay out of it's socket when it happens.)

When the OD sticks, it stays on in lower gears. I can feel the car not have the appropriate "get up". If I park the car for a few minutes, the OD disengages, and the car shifts normally.

If I flick the OD on after the car cools down for a couple of minutes, the OD kicks in almost instantly (quicker than it normally does), and the process above repeats.

Any ideas? In the past when I've had issues it's always been due to fluid being low, but this transmission is tight (doesn't leak), and it isn't low. Currently it has 80w-90 oil in it.

Thanks as always.
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