I was wondering what the usual speed you guys kick in the overdrive in? The volvo manual says 40 mpg and up?....my basic feel for the OD would say 50 and above....or 45 if going down a hill or something. What speed do you guys usually engage in?

yeah..i hear you :)

My usual highway engagement speed is 50 as well. I was asking because i realzied some people's usual speed for engagement was 40 or 45...seemed a bit low.

I've begun the habit of always using the clutch as well for engagement as well as disengagement

I follow the instructions that are in the manual that came with my car:

Here's the direct quote from the manual for my 1980 245DL:

"Overdrive (some models only)

The overdrive can be engaged in 4th gear only.

No extra operation of clutch or throttle pedal is normally necessary. Engagement is facilitated if the accelerator pedal position is maintained steady.

When disengaging, depressing the clutch pedal slightly makes a smooth transfer.
Do not use the overdrive at speeds below 40 mph (60 km/h)"

Been doing it for years. Never had any OD problems.
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If you listen to the radio in Portland, OR, you may know me as 'Portland's Favorite Soul Brother!'

I usually kick 'er in at about 80 km's or so (whatever that is in american).
I've lately been no clutch engage, but clutch the diengage. Always curious what others do.....

80 kilometers is 50 mph for the gringos here in america :)

I don't even think about throwing the OD switch until I'm going at least 50 mph.
--
If you listen to the radio in Portland, OR, you may know me as 'Portland's Favorite Soul Brother!'

Mine seems to pull OK without any strain at 35 mph upwards, on a level road. It depends what you want to do next - accelerate, or just amble along.