My auto trans 740 wouldn't shift into overdrive. I remember a thread here where someone used a wedge to permanently engage the solenoid, thus eliminating the problem. But I can't find that thread. Anyone tried this?

Or should I just spring for the IPD bypass plate? Is it difficult to install?

I suspect it was not the solenoid that was "wedged", but the relay. That armature wedging will work as long as the wiring (white wire) from the relay to the solenoid is intact, and the solenoid is good.

The relay itself can be eliminated by replacing it with a jumper wire where the relay plugs into the relay rack. The jumper would go between the two rack sockets that correspond to relay terminals 15 and 87.

IMO, the relay wedging or jumper bypass are much easier, quicker, and cheaper than the IPD solenoid bypass plate — as long as the solenoid is good.

OD operation will be automatic, but the shifter switch downshift (relay control) will be disabled.

P.S. Is fuse #12 OK? (OD, Cruise Control, and Back-up Lights)
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Bruce Young
'93 940-NA (current), 240s (one V8), 140s, 122s, since '63.

If you do not need to manually disengage the overdrive, put the bypass plate on. It will require less effort than taking the solenoid apart to wedge it open. I've been driving one of mine for 2 years now with similar modifications and have never missed the manual shift.

Regards
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Will Dallas, www.willdallas.us, www.willdallas.org, www.willdallas.com 86 245 DL 222K miles, 93 940 260K miles, 88 765 GLE 152K miles.

A correct fix might cost less than that little 10 cent piece of metal that IPD is selling for $40.
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Chris - 1990 740, 1973 1800ES (Non-running), 1993 Dodge Dakota (Still has a little paint left on it)

Just grind out the passage on the solenoid, remove the little O ring and put it back together. That is providing you have a failed solenoid.

Mark