Alternate tranny fluid for 2002 S60?

[Krons]

Sounds like with heat your valves are sticking a bit causing a rough shift, certainly no guarantee but I’d say a cooler return flush would give a good change to help the shifts smooth out.

It's no different that drain and fill. Valve body diverts only a part of ATF flow to the cooler. Fresh ATF from return line drips into sump where it mixes with the old one. No difference. Perhaps, drain&fill is even more efficient, since it replaces 1/3 to 1/2 of the fluid in one pass.

Definitely not a drip into sump on mine. It pumped out 2-3 quarts in way less than a minute, barely enough time to go through the gears on jackstands. This was on a 02 S60 2.4T FWD and 05 S40 2.4i FWD, maybe we are talking different transmissions.

I kinda wish I would have pulled the drain plug to see how much was in the trans sump after pumping 3 qts out via the cooler, would be interested to know.

[Krons]

Yeah I was just about to say the same thing. The only way to clean the solenoids is by removing the transmission sump/cover, however therein lies the problem. I either have to drop the subframe a bit, while simultaneously using a hoist or something to have the engine not drop, or someone somewhere mentioned you could jack up the engine high up(you still have to undo most if not all of the mounts.

Anyway, after driving some more today, I can definitively say the transmission is going back to a bit harsher shifts. I can't say yet for sure. Something basically changes in the properties of the fluid when you drive a bit more with the new fluid(perhaps mixing more with the old one) or the gearbox is continually re-adapting the wrong way!

So yeah if anyone has any guesses why the effect in shift quality is temporary?

Best way to clean the solenoids is fresh fluid pumping through them.

Both my cars shifted a little funky after a complete flush. I’d say flush (or drain/fill) til your fluid is clear then reevaluate after 500-1000 miles of driving.

Heat will expand and contract them so natural to have some difference in behavior cold vs hot given the tight tolerances. Fluid viscosity is different too, impacting shifts.

[dikidera]

True, heat will change things, but remember I said before that I took a 10 mile trip yesterday with the 11l flush and the car was waaay smoother, even at 93C gearbox temp(I was data logging).

Today, after driving for 20 additional miles, the shifting is not as smooth as yesterday's.

[Krons]

Hard to know when the software is learning and when it settles down. Seems mine took a while (100+ miles) to finally settle in. I recall wondering if I screwed things up with a complete flush but they both eventually came around to smooth shifting.

[vtl]

I kinda wish I would have pulled the drain plug to see how much was in the trans sump after pumping 3 qts out via the cooler, would be interested to know.

About zero. Normal drain is around 3.3 qt for me.

[vtl]

Yeah I was just about to say the same thing. The only way to clean the solenoids is by removing the transmission sump/cover, however therein lies the problem. I either have to drop the subframe a bit, while simultaneously using a hoist or something to have the engine not drop, or someone somewhere mentioned you could jack up the engine high up(you still have to undo most if not all of the mounts.

Anyway, after driving some more today, I can definitively say the transmission is going back to a bit harsher shifts. I can't say yet for sure. Something basically changes in the properties of the fluid when you drive a bit more with the new fluid(perhaps mixing more with the old one) or the gearbox is continually re-adapting the wrong way!

So yeah if anyone has any guesses why the effect in shift quality is temporary?

Sump has no pan in this transmission. The cover is for valve body. There's a pretty good howto for valve body replacement: https://www.volvoxc.com/0/resources/how ... es-bak.pdf Tedious, especially when the cover bolts are rusted out and strip. It only takes me twice longer to drop the whole transmission.

I'm not surprised this already picky transmission is not shifting well on an ATF-coolant mix.

Long term effects of coolant mixed in ATF is rust and paper separating from frictions.

Hmm, I may need to bypass the cooler. The radiator was replaced with brand new Volvo in 2018, but having no way to mix the fluids is the best prevention, I guess.

[dikidera]

Yeah sorry it was a miscommunication on my part. I did in fact refer to the valve body cover.

Now, while I do feel every upshift and downshift, I would say the 2-3 bump is the most noticeable AND the neutral stop. Neutral stop would be the transmission going neutral when braking and then re-engaging to first gear.

You are also correct about splines/cv being worn. Apart from the hard shifts, I do have thunks when stepping on or letting go of the gas. This is probably somewhat contributing to the bad shifts.

Anyway, my conclusion after driving some more is that the transmission is better than when it had mixed ATF-Antifreeze, some gears are also better than when I first got the car, but this is probably temporary. Still, I am now convinced another flush might help more, but at least 10l again.

Now according to the information on volvodiag, Volvo have specifically made a slipping lockup of 50-200RPM, I believe the lack of the Volvo specific friction modifiers has made the lockup slip more prominent basically. In 5th gear, speeds below 80km/h and throttle less than 35% I have an oscillation every 2-3 second of 50-200RPM, which would indicate a constant lock/unlock, aka slip. This does not happen at the same speeds with cruise control.

So while new fluid does help, I think I really need those friction modifiers.

Additionally this article over here mentions LubeGuard HFM and from what Google Translate says, other cars' autos are much more gentler in shifting.
Anyway I was hoping someone can read the article and tell me what it says about the additive? https://www.drive2.ru/l/621569592296221608/ cause google translate indicates he is both happy and not with each sentence.

... continued testing of lubegard
at the beginning of 8 a.m. a small trip to the countryside for 70 km
went, didn’t understand anything, it seems to be the same, it draws you into the cold, although no, it seems to be better,
and after 3rd gear you don’t feel any shifts at all, but no
CVT I managed to enjoy a smooth trolleybus acceleration, as no longer trolleybus 140!

There is also part 2 https://www.drive2.ru/l/645402331461998008/

[Krons]

I would flush first then drive at least 500 miles before adding any additives in case they aren’t needed. I typically view them as a last resort.

[vtl]

Additionally this article over here mentions LubeGuard HFM and from what Google Translate says, other cars' autos are much more gentler in shifting.
Anyway I was hoping someone can read the article and tell me what it says about the additive? https://www.drive2.ru/l/621569592296221608/ cause google translate indicates he is both happy and not with each sentence.

He is happy with the fluid.

[vtl]

I would flush first then drive at least 500 miles before adding any additives in case they aren’t needed. I typically view them as a last resort.

Coolant washes additives off. I would drain&fill and add HFM.