1987 740GLE Overdrive Question
 

Hi everyone,

I have a 1987 volvo 740 GLE (non-turbo) wagon with manual (m46) transmission. I can only engage the overdrive after a long time at freeway speeds. It stays in overdrive, but it won't engage when the car is cold. Do I need to replace the overdrive solenoid, relay, or both? Thanks a lot.

RE: 1987 740GLE Overdrive Question
 

Sounds like a wiring problem. Before replacing relay/solenoid I'd check the associated wiring-it's known to do exactly what you describe.

RE: 1987 740GLE Overdrive Question
 

Also check the transmission oil level. It should be just below the fill hole.

RE: 1987 740GLE Overdrive Question
 

When you try to engage the overdrive does the light come on, for a while before the overdrive engages? tedv is right, the wiring is a likely culprit. However, I suffered this issue for a while myself. I always had some sort of problem with overdrive not working properly. Sometimes it simply wouldn't activate, other times the light would come on, but it would take a while for the shift to occur. I did find that some Lucas oil in the transmission provided tremendous improvement, but ulitmately all I had to do was open the relay and renew the solder joints inside to rememdy all my problems. The facts are; the overdrive units are good for quite a while, the solonoids rarely fail, the switches themselves are simple and easy to check/clean, and the electrical system controlling the overdrive is flawed everywhere between the switch and the solonoid. Take a look at the wiring and the relay, you'll most likely be able to solve your problem for a few dollars.

RE: 1987 740GLE Overdrive Question
 

Thanks for the tips everyone. I'm going to look into it this weekend. I will start by checking the wiring and seeing if there are any obvious connection problems. I"ll also check the fluid level. As for now, I know the issue is not at the switch on the shifter, as I have tested the button, and done a wire to wire connection test. I might also see if the switch on the tranny itself needs cleaning or replacement. What makes this problem annoying is that it's intermittent. I have looked at the prongs on the relay which seem fine, but I haven't opened it up to see the internal soldered connections yet. I'll let everyone know what the outcome is. Nothing like a wild goose chase.