Transmission Fluid Change - Resetting Counter vs. Adaptation

[Xheart]

I am on my 7th Simple D&F of MOBIL ATF 3309 on each car.
It is close to 3.5 qt each time.

Our 2001 V70XC, 156,000+ miles shifting has gradually smoothed out -- barley noticeable now -- after 3 years of simple D&F.

140,000 + miles - the 97 850 has hairline surge remaining when shifting up from 1st to 2nd for first five minute of urban drive, after that it is as good as V70XC.

I have never reset fluid counter nor a special drive cycle for adaptation. ONLY shift back-and-forth between gears and pause as each quart was added, poured slowly. Plus the normal driving has worked for our two cars.

But then:

• VIDA says to reset counter and follow adaptation if the transmission or component such as valve body was serviced and/or fluid changed.

• The Resources > How-To for the B4 Servo Cover Update instruction ask to set adaptation for 3rd gear only.

I am concluding that fluid counter reset and/or a strict drive cycle is not necessary for a DIY simple D&F.

Any feedback to help correct this DIYer's assumption is appreciated. I am looking forward to 200,000 mile marker on each car.

Happy Spring!

[kutcht1]

I guess I am also with you as I did the drain and fill all in one shot with 12 quarts. Draining 2 quarts at a time, then filling. I did this when I first got the car as I do this with every used vehicle I get my hands on. I had not heard about this adaptation procedure until reading on further on this car. The vehicle has been shifting great since as I only had ran through the gears after each 2 quart drain/fill and then drove the car for the next year. If the adaptation really is needed or makes the computer shifts better I have not noticed not having done the adaptation. On the other hand, it is very cool technology if it actually does something.
TomK

[JRL]

You really need to reset the fluid counters according to ALL the mechanics at my dealership (which is a knowledgeable one).
You have VIDA just do it.

If it's shifting fine, adaptions are not necessary (also my dealer, in fact now they're shying away from adaptions except in certain cases).

[2002V70XC]

I don't think resetting fluid counter is a big deal at all. I think this transmission is always on learning mode even after the adaptation process. The Trans shop did a 10 mins adaptation after doing the VB on my car. When I picked up the car, the guy explained to me that it would take time to settle and it would drive not so smooth for a few hundreds kms. That was true, it drove like a truck with manual gearbox (just like when you are performing the adaptation) and then it got smoother after a few days. My point is that if this trans continues to learn to adapt so that it can perform at best, it shouldn't have problems with bad shifting data being stored previously because it should always learn and adapt.
Of course you need to make sure you have the perfect level of ATF. Too low or overfilled would be a problem.

[vtl]

If I remember what is written in VIDA, counter is increased when ATF was absurdly hot (like +150C/300F) for absurdly long time (like 3 minutes). When counter reaches some point, TCM makes conclusion that ATF is cooked, and changes shifting strategy: torque converter lockup is applied as often and as soon as possible to avoid slippage, which will destroy TC in presence of degraded mineral oil. Now, if you never drove 120 MPH for like half an hour, and the car never was in multi-hour stop&go traffic in 120F weather, it's hard to imagine that counter increasing.

[2002V70XC]

Does it mean that the counter can only be increased but not decreased? I just don't understand whether it counts the number of occurrences or it is doing something else. Does the counter have anything to do with the shift strategy when ATF is healthy?
I understand that overcooked ATF would cause all sorts of problems.

[vtl]

Counts number of occurrences. Does nothing to shifting until counter reaches some threshold.

[2002V70XC]

Counts number of occurrences. Does nothing to shifting until counter reaches some threshold.

Cheers!

[Xheart]

Counts number of occurrences. Does nothing to shifting until counter reaches some threshold.

What is counted for occurrence?
Is the threshold #of occurrences, e.g. 2000 occurrence of ________________ .

[brenglxc70]

I've read a few threads similar to this on Volvo forums, and the consensus amongst Volvo enthusiasts seems contradictory to what I have learned in all of my other automotive exploits. If the trans is shifting "smooth", then there is a lot of slippage going on during shifts. Slippage=friction=heat. Heat is the enemy. Firm positive shifts with minimal slippage are easier on the transmission and less heat is generated.

Maybe I am misinterpreting what is meant by 'smooth' shifting here? To me that means slushy, slow shifts so you do not feel the shift.