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Overdrive Problem; Won't Engage


Freshman Member
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Had weird similar problems. Solenoid intermittent even with new solenoid.. turned out the 3-4 trans switch must have corroded internal contacts, ohms varied randomly between 10-60 ohms when closed which randomly activated solenoid.. replaced switch and works fine!


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Hi Skip,
As Tracy said, while you are driving, transmission cover off, when you switch into OD, try pushing the lever on the RH side forward more fully into the engaged position.

There is some slack in the lever/solenoid travel which may make the travel marginal. If this works, the lever/valve needs adjusting for more travel, likely only a tiny amount of additional travel. There is a more precise method of setting the lever but this might get you by for now.

Put a piece of cardboard over the transmission rear & U joint to keep it from throwing grease all over & to keep your shirt tail out of the moving parts.
Dave....you seem to know things🤗. My BJ8 has this problem. When in overdrive 3rd, if a I press gear lever forward very slightly, the gearbox is disengaged. ???

Bob McElwee

Jedi Warrior
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Dave passed many years ago but was very willing and knowledgable helping us. The comment about the moving parts is important. You are very close to a spinning U-Joint.


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Dave....you seem to know things🤗. My BJ8 has this problem. When in overdrive 3rd, if a I press gear lever forward very slightly, the gearbox is disengaged. ???
Now sorted......gear lever switch not quite engaging itself because of wear. Adjusted sw


Jedi Knight
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Glad that you sorted the problem. I had a similar OD non-engagement issue and determined that it was the 3+4 gear transmission switch. I was able to remove and replace the switch from under the car without removing the transmission tunnel, after which the OD engaged as it should. The plunger ball on the old switch was very worn.
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