Volvo 850 2.0 Automatic ATF transmission oil recommendation?

[expandingmaan]

Originally Posted by RollingThunder

The most important thing to remember is to use the correct grade of ATF. Use ONLY Dexron II or III in your gearbox (it'll be an Aisin Warner 50-42 of some variant - you'll see the serial number and type on a plate on the top of the gearbox)

I've had the pleasure of changing ATF on a few 850/x70s with this gearbox. As mentioned ^^^, one method is to remove the top transmission line from the gearbox to the radiator. You attach a length of hose to the end of the rigid line and put the other end in a receptor of some kind (I used a 2 litre coke bottle). You start the engine and the ATF fluid comes out of the hose into the bottle. By marking 1.5 litres on the bottle beforehand, you know when to stop the engine and how much new ATF to add (down the ATF dipstick). You need to move the gear lever through each position (holding the footbrake down of course!) to ensure that the fluid is flushed through all the gearbox galleries. The fluid coming out is under low pressure - its like a running tap, so don't be afraid that it'll squirt out everywhere like an artery The last car I did a fluid change in this way, I used almost 20 litres (!) But I did keep going for a while after it appeared clean, 'just to be safe'.

I changed the ATF in my current car, a '96 850R with the same gearbox using the 'drain sump and refill' method a few weeks ago. This is supposed to be 'kinder' to the gearbox, as the old fluid is slowly diluted in fresh ATF with each sump drain/refill. I'll expand on this a bit later...

So what you do with the drain sump method is warm the ATF by going on a 10-15 minute drive. This will also ensure that the debris in the ATF is floating in the fluid and not stuck in the bottom of the sump. You then drain the gearbox sump (24mm sump plug) using a 5 litre or so container to catch what you drain. Let it all come out - there will be between 3.0 - 3.5 litres of ATF released. Refit the sump plug using a new washer (washer is the same as the engine sump washer). Pour the dispensed fluid into a jug and measure how much has come out - put *exactly* the same amount of fresh ATF into the gearbox via the gearbox dipstick tube (note - you'll need a suitable funnel that is narrow enough to fit into the dipstick tube, and long enough to reach it!). You then drive a few days to make sure the new fluid is fully mixed in with the remaining old fluid and repeat the process again. You then to do a final drain/refill one more time (ie 3x times overall) which in theory will have replaced 87% of the old ATF.

Which do I prefer?

The hose removal method means that you need to buy a new retaining clip and new o-rings. These are surprisingly expensive - they might cost £20 or so IIRC? The advantage is that its all done in an hour, and you can see how much better your fluid is looking.

The drain/refill method takes several cycles of drain, measure, refill, drive...etc but its an easier task overall. But it takes a while as you have to do it over and over.

Personally I prefer the drain/refill method, but thats just my preference.

Which takes me back to that contentious argument that the hose removal method can kill your transmission! I think this is a bit of a red herring to be honest - this is my view and is not supported by any scientific research whatsoever!

It is normal for the clutch plates to wear in an auto gearbox - they are very similar to the clutch plate in a manual gearbox. When you check the auto gearbox sump plug, you'll see that it has a magnetised internal end which will have a surprising amount of black debris stuck to it - this is worn particles of the clutch plates that were suspended in the old ATF before being caught by the magnet. With this old fluid being forced between the clutch plates, these particles are actually giving a bit of added friction between the plates. Once you remove all those particles through replacing the dirty ATF with nice fresh clean ATF, that added friction is no longer there, so the clutch plates no longer have that assistance. If they're badly worn, that difference could be enough for the drive to fail - hence many people have stated that a fluid change has killed their gearbox. IMHO that is not the case - it was already badly worn and needed new clutch plates before the fluid change anyway. It would have failed once the debris could no longer give enough friction assistance to allow the drive to be transmitted - but would be behaving badly long before then.

So, again IMHO, there is no difference in risk between either method. Just use the correct fluid, new washers and be utterly clean in everything you do - you definitely don't want to be pushing dirt down the dipstick tube

Hope this has helped.

NB The ATF I used was -



Yes, I'll be running 12-15 litres through...

Thank you ever so much for taking your time out for such a lengthy reply.
You now got me thinking twice about changing the transmission oil. I may postpone it and enjoy the car for a little while before changing the fluid (just incase it leads to some sort of premature failure).

Kind regards

[expandingmaan]

Originally Posted by Clan

Just get the correct oil from the volvo dealer :

Dextron II E ( Ford Mercon)
1 litre PN 1381166
4 litre PN 1381167

thank you, I may give the local dealer a ring and see if their oil is cost effective.

[expandingmaan]

Originally Posted by RaelG

Potentially stupid question, but why change the oil in the gearbox at all? Are there symptoms of wear or imminent failure or is it purely preventative?

for myself, its preventative wear. Furthermore the oil doesnt seem to have been changed throughout its life span, so it seems it is begging for a change.

[RollingThunder]

Just for info, I'm doing the change purely for preventative maintenance purposes. It is amazing how dirty ATF becomes over the years/miles.

This is a pic of the fluid taken out of my current 850R at 84k miles or so:



Bear in mind that should be like cherryade - a translucent red/pink, not brown.

And this is what I drew out of one of my old V70R's - this one had approx 120k miles up - I changed the fluid in this car using the 'remove rigid line' method:



As an aside, Toyota, who used an almost identical gearbox in the Camry V6, recommended an ATF fluid change every 50k miles IIRC - this is a vague recollection, but one that is quite persistent, so I believe it is true. (Apologies, my post covid memory is shocking lol)

[richmac]

Interestingly, if the Service Schedule in the following link is indeed correct, Volvo recommend a fluid change every 40,000 miles.

http://www.volvohowto.com/volvo-850-...cheduled-plan/

[RaelG]

Thanks for the replies. Actually this whole topic has got me wondering whether I should do mine. I had no history with the car and it’s on 111k now.

My first to second change is a tiny bit jerky unless under a bit of load, is this a sign of wear or just a characteristic perhaps?

[RollingThunder]

Originally Posted by richmac

Interestingly, if the Service Schedule in the following link is indeed correct, Volvo recommend a fluid change every 40,000 miles.

http://www.volvohowto.com/volvo-850-...cheduled-plan/

I've never seen it mentioned before! If that is the original, un-adulterated schedule then that is very interesting! Thanks for the link.


Rael - I would recommend a change at 80k miles max, ideally every 50k.

I'd expect your ATF to be quite brown by now, and as the ability of the fluid to deal with heat will have deteriorated, it'll also probably smell a bit burnt.

Although the gear change in my car was already pretty smooth, its feeling even better after just one drain/refill change. The AW50-42 is a particularly smooth gearbox - the changes should be barely perceptible, so if you're having a nudge when changing gear, its time to change the fluid - IMHO

[RollingThunder]

Did the second drain/refill today - about 200 miles after the first cycle. The ATF drained today was as bad as the original stuff At least I know all the debris is coming out, albeit slowly. Looks like I'm going to be using all 15 litres that I bought!

I'm keeping small samples of each drain and I'll put up a pic showing them all once the final cycle has been completed.

This is the funnel that I use, just in case anyone else is interested in getting one to do the job. Its spot on - the small end fits into the dipstick tube perfectly and the long tube bends around obstructions nicely.





I got it off Amazon IIRC, it was quite cheap too which is a bonus.