Overdive for 4-speed `84 240DL Wagon

Hey all, 210k miles. Overdrive is working less and less.

I already gutted the relay. Overdrive is hardwired to a heavy duty switch I pulled from something on the Apollo program. The overdrive will enguage sometimes if its cold out. Once the car warms up it seems less likely to work. If its like 60 degrees out, it sometimes will enguage if I'm going 70 up a hill and floor it. Less and less likely though. That used to be surefire.

We've replaced the tranny fluid ~30k ago. There's a magnetic filter we clean fairly regularly. I think we even replaced the solenoid itself like 60k miles ago. All these steps "felt" like they were making it better, but for every one, 10k latter it was just as bad as it had been.

It keeps getting worse. It used to enguage basically no-matter-what in the cold. Now once the car starts warming up, it doesnt seem to want to enguage.

I'd really like some advice on this. with a working OD, the car would be great.

Rektide

Reply to
rektide
Loading thread data ...

Internal to the OD are two O-rings that after a hundred and sixty thousand miles or so will start to no longer be able to contain the pressures necessary to engage the OD.

Cold fluid is thicker than hot fluid so the OD will work when cold but not when hot.

The only true cure is replace the two offending O-rings, whihc requires removal of the OD from the tranny. The tranny can stay in the auto.

See:

formatting link
a how to description. Duane

Reply to
Duane

There's a set of seals inside the OD unit, IPD sells a rebuild kit for it.

If you don't like the relay, you could always use the pre '81 arrangement with the heavy slide toggle in the shift knob, though I personally like the relay better.

Reply to
James Sweet

MotorsForum website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.