940 auto transmission glitch

[760Simon]

Dave,

I need to sump dump the S80 ( AW 55-50 gearbox which requires JWS 3309) as its starting to get a bit harsh and this time a spot of treatment to help, i thought at the same I'd treat the 760 to a couple of sump fulls of fresh stuff to make it smoother

[stegreg]

Right, Iv managed to do a further partial oil change, this time by removing the oil dipstick off the sump pan, so did get a bit more of the old oil out.

have to say, its still not changing/locking in to 4th, still doing the "slip in to 4th on over run" thingy bit, but the moment you touch the throttle to maintain speed, it slips out and lockw back to third.

Now, my overdrive solenoid has arrived from the states, not yet fitted, but suspicious of possible contamination inside this, possibly holding the valve plate partially open? has anyone had this occur before, rather than it stick fully open?

OR has the relay got issues with possible weak coil? afterall, itss as old at the car, 1995. I do have a new replacement for this too, BUT where is it? I cant see a white coloured relay in the panel behind the fuses, only the white fuel pump one on left. the relay that is sitting in situ where the books seem to suggest it sits in the relay panel is a black relay, but twice as wide as a normal relay, more oblong that square.

OR being as this is an "SE" model.version, is the overdrive relay mounted somewhere different and not in the main centre consolde fuseboard?

[Laird Scooby]

How much new fluid has it had now?

[stegreg]

ive used 4 ltrs [one tub], still have a second....er did buy some backup, knowing would need to do a better/fuller flush later on.

[Laird Scooby]

What sort of spped are you doing when it goes back into 3rd?

Also that's really only one part-change, make sure the suction hose from the extractor pump is as far down the dipstick tube as it can go and let it run until it doesn't pull any more fluid, should take about half hour and remove 2.5 - 3.5 litres.

Then give it at least 100 miles before anything else, it's not an instant "magic fix".

As for the relay and solenoid, if you start messing around with those and then the fluid changes fix the fault, you won't know what actually caused and/or fixed it.

[stegreg]

Speed wise, id say its around 50 -60mph, just ease off the throttle and you can see the revs drop, then sort of "hover" arround 1200rpm lower. but if you then touch the throttle to hold that speed, the revs pick back up again.

Ok, will stick with oil flushing, but would it help any if I get a replacement sump pan gasket, then drop mine off,remove and clean out the oil strainer plate.....being as cant get new now from Volvo, just incase some of this yucky black stuff is really sticking to the strainer mesh.

all other gears are fine, change smooth, both up and down the box, even reverse. No harshness or backlash whatsoever. when pulling off from standstill there is no delay, or hesitancy, torque converter is working well.

[Laird Scooby]

I doubt getting a sump pan gasket and dropping it off to see if the pick up is blocked would be any use at this stage for the simple reason that it works fine through the rest of the box. Might be worth a go though, just to be on the safe side.

From the sounds of things, it's an AW-71 of some description, is it an AW-71, AW-71L, AW-71 E or AW-71LE?

Also i'm wondering if perhaps the kickdown cable has come out of the box and is now holding the kickdown cable tighter than it should be or maybe kinked somewhere.

[stegreg]

I would have to look see if I can see an ID plate on the box to get the exact "AW71" identity, I did originally slacken off the kickdown cable slightly and give it a little more slack at the throttle drum. I did try manually pulling the caable to make sure it wasnt snapped/frayed....there is a little resistance on the caable, but it returns to its original position easily and quickly.

I really need to get right underneath the motor, once the weather picks up a bit, way too wet here currently to do much on the floor, as dont have a dry garage to play in, only a driveway. have a look at the kickdown cable and its routing, as well as look for the id plate.

[Laird Scooby]

Al-fresco workshops are great in the summer when it's warm and dry but lousy this time of year when it's raining, sleeting, snowing and blowing a Force 9 up the back passage!

[760Simon]

Stegreg,

Save you getting wet and cold take a look at this page it might give you some help

https://www.volvoclub.org.uk/vin_700.shtml

cheers

this may also help

https://i.pinimg.com/736x/3b/69/08/3...gle-search.jpg