Transmission Service-What do you think?

[dtlayman]

Thought we would poll ya'll and find out what everyone thinks should be done to maintain this very important part of our car.

[gibbons]

Volvo seems to imply that the trans is a never-needs-anything device, although the processor does keep tab of operating hours and harsh conditions and can pop up a service message if parameters are met. In my completely unqualified opinion, I think it's important to flush out and replace the original ATF at a relatively young point in the car's life. I did ours myself at 15K miles, as described in a thread I started some time ago. Doing this flushes out all the abrasive, microscopic particles that wear off the gears and clutch plates as the transmission is breaking in.

Second, make sure that your car has the latest, greatest transmission software so that the shift strategy algorithms are the best to date. I had mine updated and it made quite a noticeable change in the way the car drove and shifted. Shifts were more crisp with less slip, it seemed. In another automotive life, I have learned that the crisper the shifts (within reason), the longer a trans lives because the clutch pack doesn't slip as long per shift.

There is no filter to change. Other than that, drive normal. I think.

[BillAileo]

I concur with Gibbons comments although I waited till about 35,000 to change the fluid. Just make sure you are using the correct ATF, its not the same for all years. The later models use 3309 as has been discussed in other threads.

Bill

[dtlayman]

I just recalled that we had the valve body replaced around 35,000 miles. Am I correct to assume that they have to replace the transmission fluid when they do this?

[dtlayman]

I spoke to the indepent shop today and he told me that they needed 16 quarts to do the flush. I told him that the capacity is closer to 8 quarts but he said it would take 16. I ask him what kind of fluid they used and he said "BG". I said that I had been told that Volvo says only to use their oil and this oil is Mobil 3309 and he said this "BG" is approved by Volvo. He said about $120 for normal flush but on this car because they have to use synthetic is about $80 more - total $120.

I also ask how they flush and he said they use a cleaner first and that they don't use a machine - he said they could do it faster without the machine. He said they had all of the parts - o-rings, etc. that they need.

I looked up BG on the internet and it seems to be some sort of franchise package of services. Anybody familiar with this?

[BillAileo]

At a minimum, I would want to see something in writing on the containers of transmission fluid showing the fluid met the 3309 standard or I'd go elsewhere.

Bill

[gibbons]

I always get nervous around "cleaners", which are either solvents or detergents whose job it is to break down the ATF and any of its residues. If you don't get it removed perfectly, then you have some residual to attack whatever you put in new.

[Raynald]

I just recalled that we had the valve body replaced around 35,000 miles. Am I correct to assume that they have to replace the transmission fluid when they do this?

Yes. They did mine (under warranty) and they had to flush the tranny and put new fluid in.

[dtlayman]

I have an independent shop that insists that BG sythentic transmission fluid is the correct fluid for this car. I ask him if he would do a transmission flush with the Mobil 3309 and he said don't you trust me, etc. Does anyone know about this BG product and whether it meets the specifications? This is a small town without a lot of choices and I don't want to burn a bridge with this shop insisting on the use of the Mobil 3309 if the BG product is ok.

[BillAileo]

The BG stuff may be great, but I get a little concerned when their website doesn't appear to offer any specification information and your loal shop doesn't appear to be offering details either. You've got a car with an expensive automatic transmission, you need to know exactly what's being put in it.

Bill

[Ron3KL]

Folk who are considering flushing the transmission fluid in their XC need to be aware that part of the operation may require connection to VADIS if the procedure is to be done according to Volvo's instructions. This information applies to at least the 2002 model - don't know about other years.

There are two reasons for doing so:
1) Adaptation of the Transmission Control Module (TCM) to the fresh transmission fluid, which requires connection to VADIS followed by a test drive; and
2) resetting the transmission fluid change counter.

Here are the quotes from Volvo's transmission control module overview:

Adaptation data

There are two functions for adaptation in the Transmission Control Module (TCM) software which can be activated:


Resetting adaptation - carried out after replacing internal components or the entire transmission
Adaptation function - This function helps the mechanic to adapt the transmission. It makes it easier to reset the function of the transmission after repair or replacement of, for example:
the transmission control system
the transmission fluid
the entire transmission
the Transmission Control Module (TCM) .


When the adaptation function has been activated, the test drive instructions must be followed. The following shifts can be adapted:

1 - 2
2 - 3
3 - 4
4 - 5
N - D
5 - 4
4 - 3
3 - 2
2 - 1
N - R
Neutral Control engagement and disengagement, if equipped.


While the car is in this mode, the orange/yellow warning lamp in the center of the combined instrument panel is used to indicate when each shift has been adapted to its target value. When the orange/yellow warning lamp (triangle) flashes after each of the listed shifts, the adaptation is complete.

Note! The function is only available in certain software versions.

Adaptation of the transmission is activated via the VADIS vehicle communication socket.

and


Counter for transmission fluid data

A counter for transmission oil quality is built into the software for the Transmission Control Module (TCM) . The counter counts up the amount of time the oil is above a certain temperature. When the counter has reached the maximum value, the Diagnostic Trouble Code (DTC) for an oil change is stored in the control module. When replacing transmission fluid the counter must be reset to prevent a Diagnostic Trouble Code (DTC) being stored incorrectly. This applies when the transmission fluid is changed and when the fluid is changed during a repair.

[bouvier]

We had the " transmission service required" indicator at about 15K miles on our 03. Turned out to be a computer glitch and the soft ware had to be reloaded. It took two dealers three tries to get it right.

Bpouvier.

PS: Ran fine during this time and still is.

[dtlayman]

Are there any risks involved with a transmission flush? We spoke to one independent shop and they said they didn't like to do the transmission flush at the 30-35k interval but liked to perform drain 4 quarts and fill every 20k or so. He said he liked to check the quality of the oil and monitor at these intervals but seemed to indicate there was some risk with flushing.

[Bandit1]

Change mine out every 30K. The reason they need 14-16 quarts is because that is what the machine needs to do the transfusion. BG is an excellent product line. I use their fuel injection cleaner at regular intervals (BG44K), but you do not have to use a cleaner when you do the tranny transfusion. Its just another additional charge in the tranny flush procedure. Unless you use your prized possession for constant off roading and/or racing, a chemical flush is pretty much not needed. [nonono] Just give it some new mojo.

[budrichard]

Why would one do anything other than what the Volvo Service Manual that came with your vehicle reccamended? A little knowledge can be a dangerous thing. Does anyone think that they understand the operation and engineering better than volvo?
According to my 2003 Service Manual, Volvo Only reccamends changing the fluid every 52.5K miles if you use the vehicle for towing.
My 1987 Volvo GLE is still going strong at 275K miles and I don't ever remember changing the fluid. Same thing for my 99XC at 95K miles.
There is too much amateur thinking going on in this forum, that may in fact be detremental to vehicle operation. I am shocked at the original question and the fact that NO ONE thought to look in the SERVICE MANUAL!-Dick

[philosophicaldreamer]

Why would one do anything other than what the Volvo Service Manual that came with your vehicle reccamended? A little knowledge can be a dangerous thing. Does anyone think that they understand the operation and engineering better than volvo?
According to my 2003 Service Manual, Volvo Only reccamends changing the fluid every 52.5K miles if you use the vehicle for towing.
My 1987 Volvo GLE is still going strong at 275K miles and I don't ever remember changing the fluid. Same thing for my 99XC at 95K miles.
There is too much amateur thinking going on in this forum, that may in fact be detremental to vehicle operation. I am shocked at the original question and the fact that NO ONE thought to look in the SERVICE MANUAL!-Dick

First of all, there is nothing wrong with questioning stuff. This is how progress occurs. Knowledge is acquired when dogma is questioned.:) Second of all, I am one of those who thinks that there are no stupid questions, only stupid answers. Thirdly, I wouldn't be so trustful of any manual. When I had Volvo 965 and V90, both manuals were telling me that I never needed changing the tranny fluid. When I showed it to my mechanic, he laughed and told me that it sounded as though Volvo thought that their fluid was immune from deterioration, which obviously was incorrect. Anything deteriorates with time and use, even diamonds :D Just because something is in print does not mean that it is true. Take a walk to your local transmission shop and ask them what is one of the most common reasons for transmission failures, and I am sure that they will tell you that it is lack of tranny maintenance. Think of ETM issue. Volvo claimed for years that there was nothing wrong with ETMs either. Well, they were wrong. Engineers do make mistakes all the time. History is replete with engineering disasters.

Ta-ta, j.

[Pennhaven]

First of all, there is nothing wrong with questioning stuff...Engineers do make mistakes all the time. History is replete with engineering disasters.

Not to mention the fact Volvo trusts their own maintenance advice so much that they warrantee the transmission for a gigantic 36,000 miles. Wow. Really confident aren't they?

Then if it fails after the warrantee expires Volvo and their dealer get to charge you how many $1,000 (anyone here know?) for a new transmission. Realistically from a business perspective it would seem that Volvo doesn't have a whole lot of incentive for the transmission to last much longer than it is warranteed for.

While some folks who are overly obsessive about preventative maintenance, and spend more than is necessary, being a little more conservative than the manufacturer recommends is probably a good thing if you plan to keep a vehicle for any length of time. Look at it as cheap insurance.

[philosophicaldreamer]

Not to mention the fact Volvo trusts their own maintenance advice so much that they warrantee the transmission for a gigantic 36,000 miles. Wow. Really confident aren't they?

Then if it fails after the warrantee expires Volvo and their dealer get to charge you how many $1,000 (anyone here know?) for a new transmission. Realistically from a business perspective it would seem that Volvo doesn't have a whole lot of incentive for the transmission to last much longer than it is warranteed for.

While some folks who are overly obsessive about preventative maintenance, and spend more than is necessary, being a little more conservative than the manufacturer recommends is probably a good thing if you plan to keep a vehicle for any length of time. Look at it as cheap insurance.

Your point is well taken. Although I would say that maybe it is in Volvo's interest to make sure that our transmissions do not fail so quickly if they wish to have returning customers. I know that one of the reasons I buy Volvos is that they last for 200K or 300K miles without engine or transmission going to pieces. If my Volvos were falling apart at 100K miles, then I would consider other brands, too.

[Pennhaven]

Your point is well taken. Although I would say that maybe it is in Volvo's interest to make sure that our transmissions do not fail so quickly if they wish to have returning customers. I know that one of the reasons I buy Volvos is that they last for 200K or 300K miles without engine or transmission going to pieces. If my Volvos were falling apart at 100K miles, then I would consider other brands, too.

No argument. My sole point is that Volvo doesn't stick their neck out very far when it comes to standing behind their product, yet BudRichard advocates that we ought to have total confidence in their maintenance guidelines.

[BillAileo]

Dick has a point in regard to following mainenance schedules but I think the period of the warranty for the vehicle's components has to be considered as well. With the amount and complexity of the electronics and other components in today's Volvos (and just about everything else) the likelihood of getting to 250,000 miles without a major infusion of cash is decreasing. Becoming more proactive (perhaps excessive) in maintenance can, in my opinion, improve one's odds, particularly if one likes to do their own work. Incorporating transmission fluid changes is one such step. It certainly isn't going to be a negative. Besides,we know that Volvo knows that the transmission may well eventually need fluid changes because it has incorporated warning messages to that effect when certain unspecified conditions have been met.

Bill

[philosophicaldreamer]

No argument. My sole point is that Volvo doesn't stick their neck out very far when it comes to standing behind their product, yet BudRichard advocates that we ought to have total confidence in their maintenance guidelines.

Well said. Right on the money :)

Ta-ta, janusz

[budrichard]

I stand by my original post. I have two other Volvo's for experience.
From an engineering perspective, one goes to the Original Equipment Manufacturer (OEM) for maintenance information which is contained in your Service Manual. To think that Volvo has some motive behind not letting the owner know those intervals is paranoid.
To believe you local transmission shop is not smart on your behalf. These shops pray on individuals that don't understand transmissions.
A transmission drain and refill and/or flush is prone to errors. A sealed system that has the original fluid in it is preferred if the vehicle is operating normally.
I have done trans flushes on other vehicles and it is not a simple job if one endeavers to not introduce dirt or contaminants.
Other vehicle intervals have increased substantially and so has the transmission. In fact under normal conditions, there is no interval.
To attempt to perform preventative maintenance on a system that needs none is not smart. -Dick

[howardc64]

I wonder if the software programming issues on the P2 car's transmission may introduce more wear than fluid. Driving style probably can cause more wear also.

This said, we are typically taught that fluid = life blood of the car. When I called the dealer about my tranny flair issue a few days ago. His first question was "how is the color of the fluid?" So the dealer service personel themselves are trained by history besides Volvo.

I suppose a scientific test would be to pump some fluid out and send it to a test lab for results. Surely, the tranny's hardware and software design, driving style all factors in. Furthermore, what is defined as good or bad result? It depends on how a particular tranny's design is tolerant to the changing composition of the fluid.

So what does one do under this circumstance? Probably error on the side of being conservative and maybe even flush out perfect good tranny fluid. From drain ATF + refill 50% to complete flushing. As long as the service itself doesn't cause more harm. We have no evidence that it does. But I'll admit we don't have much statistics or science behind what we are doing.

It is a little hard to trust the user's manual + even the Volvo's service bulletins after watching the ETMs and tranny flare issues. The first (and the cheaper) step didn't work well in either case. The wear on the components maybe greater while these issues are getting resolved. We'll never know.

[philosophicaldreamer]

I stand by my original post. I have two other Volvo's for experience.
From an engineering perspective, one goes to the Original Equipment Manufacturer (OEM) for maintenance information which is contained in your Service Manual. To think that Volvo has some motive behind not letting the owner know those intervals is paranoid.
To believe you local transmission shop is not smart on your behalf. These shops pray on individuals that don't understand transmissions. -Dick

First, I don't think that I ever suggested that Volvo had some ill motivations behind their transmission maintenance policy. I just think that their motivation is based more on a business model than common sense. It is much easier to sell to a potential client a car in which you do not have to worry about the maintenance of transmission. But as Tom and Ray argue "A transmission fluid and filter change is never harmful, no matter how many zillions of miles you have on the car or how many fish scales you have in there." Second, I would never take my Volvo to a transmission place to have it maintained. I have an independent Volvo mechanic who has been working on Volvos for twenty-something years, and I believe him when he says that it is balderdash when Volvo claims that you never need to change transmission fluid. He tells me that "we may argue how often you should change transmission fluid, but there is no argument that the T. fluid should be changed from time to time, especially if you intend to keep your car for a long time." He maintains that he has seen number of transmissions that have failed because people did not service them. And trust me on it that he is one of those mechanics who have built his reputation in the area on not gauging people on unnecessary repairs. However, I do recognize your point that we should pay attention to Volvo has to say on the issue. But like with anything else, a healthy dose of skepticism never hurts. I am as likely to believe Volvo as I am to believe my Volvo mechanic who works on these cars day in day out. Like any other corporation, Volvo does not have a monopoly on the understanding of their own product.

Ta-ta, j.

[brider]

This has been a VERY interesting discussion. From someone who is new to the Volvo world: How long has Volvo NOT specified a fluid change interval in their auto trannies? And regarding the vehicle warranty, I thought the original was 5 yr/50k miles? Didn't this apply to the tranny also?

Did any such maintenance schedules change when they were bought by Ford? I mean, when there WAS an interval, how long was it?

I have a '97 F150 4x4 also, and I recall that there is no fluid change interval for the transfer case, which is sealed and filled with Ford-spec synthetic fluid (somebody correct me here, I may be wrong).

Does anybody understand the design of the Volvo trannies? Are there in fact internal friction surfaces subject to wear and contamination of the fluid?

I'm on the fence on this issue. While I agree that an oil change CAN'T hurt, I am intrigued by a design that is maintenance-free. I think it's possible, as long as the tranny build and quality is to such precision that internal friction is almost nil. I'm inclined not to worry so much now on my '03 with 85k miles.

TB

[Raynald]

Since the Volvo AW55 50 Geartronic is in fact a japanese made Asin-Warner transmission and is used by many other automakers (see this document (http://www.transtec.com/npa_trans/Trans-NPA0502.pdf) from a company offering an overhaul kit...), it would be interesting to know from some of them (including Aisin) what is their recommended maintenance schedule, if any. :confused:

[BillAileo]

It also relevant to consider that:
- Volvo does not say never to change the fluid and actually notes that some uses, such as towing, will generate a need for fluid flushing.
- VADIS includes instructions on how to flush the transmission fluid.

[Forkster]

Personally, I would visit your local Volvo dealer or independent Volvo repair shops and buy the correct fluid - one that says Volvo on the side.

Flushing your tranny? Are you hauling 3000lb trailers daily? Do you drive your car like it's in a rally? If not, you could be wasting your time doing a 'flush' - there is nothing wrong with simply draining all the fluid, and replacing it. I would 'flush' the tranny if I was hauling trailers perhaps every 2 years. But for every day commuting, or grocery /soccer mom hauling, it is not worth the effort or $$$. But that's just my opinion.

[MoeB]

I agree with you on the "flush" thing, but I have to disagree with you about "the correct fluid." I refuse to pay $20 for a $5 bottle of oil just because the bottle says "Volvo" on it. Even my local dealer uses Mobil ATF 3309.

[mbsl98]

After following this thread for a long time, I have to add a couple of thoughts. For those who claim to never have changed their older Volvo trannies, per volvo recommendations, and have 2xx gazillion miles: Volvo actually did specify both fluid and filter changes at 30k intervals right up to the introduction of the 850. At that point, they removed the filter and said no more changes needed in normal use (ever). As far as I know there is no magic going on inside the newer trannies - they still have friction wear, contamination, age, etc effecting the fluid, but no longer have a nasty filter plugging up and requiring changes. For those of us who had / have 850's and first vesrion S/V70's, there is lots of empirical evidence of the need for regular fluid changes. The first time for me was with our '98 XC that had severe harshness whenever the torque converter would lock or unlock, at 35k of easy use. Three trips to dealer who said nothing needed, don't change fluid, and finally a change of dealer to one who said - No problem, we see it all the time. Just needs the fluid changed (under warranty). Sure enough, a complete cure, and no recurrance with regular changes from then on. (still smooth today, owned by a friend). All of our other 850's (3) clearly had improved shift smoothness after changing fluid. Each of these was used, and we were the first to change it, at between 50 and 80k, and none of them had particularly nasty looking fluid. On our 11th Volvo, the new '07 XC70, I can't imagine why we wouldn't continue to change the fluid now and then. Note that Volvo doesn't say "do not" change, just that no change is needed in "normal" use. To me that says they see no particular issue in changing the fluid with proper techniques, just that Volvo doesn't think the extra bother is required. We live in Boston, where most driving conditions would fall into the more severe category in any case, just from traffic congestion and weather, and we also tow a boat trailer on occassion - by itself a trigger for Volvo's recommendation of 52K changes. Bottom line to me: Volvo has backed off the frequency of suggested fluid changes, but has in no way sugggested that they can hurt or should not be done. I find the idea of keeping the fluid cleaner and less filled with friction causing contaminates to be just to compelling to skip just because volvo says you can probably get away with it.

[ltoolio]

I voted on a complete flush/fill at 50K/60K, but will probably do a partial drain & Fill between my next major flush (which is still 50K miles away).

I figure that putting 3 fresh liters in after draining 3 dirty liters won't do any harm (as long as I'm cautious in my drain & fill), and will hopefully help keep things inside happy.

[KCsXC]

I vote Flushing. I have done it twice now and it is especially easy with the P2's, even easier than changing the oil because you do not need to jack up the car. I also do not believe in the no filter idea either so I installed a magnetic particle filter (from IPD) inline with the upper rad connection. As well I have performed the Bevel gear and rear differential changes and if you have never had it done I highly recommend it. I had 125000 kms and needless to say the fluid was quite dirty.

KC

[ovlovpumpkin]

i agree with having it flushed early on in the life of the transmission. i just had mine done at about 71k when i had the software updated. it was more of a preventative maintenance measure. the car does shift a lot smoother now. i would recommend doing it at around 50k though.

[PierreC]

Did a tranny flush this morning - my first, at just shy of 70k miles (110k kms). I had only recently discovered this forum, so I was totally ignorant of the need or the possibility to do it.

Briefly, I pumped through 16.1 litres of Toyota T-IV ATF [the four litre cans contain about 4.1 - 4.15 litres, thank heavens!] using the Gibbons method described elsewhere. The dark chocolate coloured fluid with dreges settling in the bottom of the measuring cup was enough to convince me - I will do this regularly from now on.

The difference? Most noticible smoother shifts, in fact, almost back to imperceptable shifts.

The use of the Toyota T-IV? Well, Toyota uses the same tranny in some Lexus models and specify T-IV for those. The spec sheet - and advice from many good readers of this forum - convinced me that T-IV is OK (and less than on third of the price of the Volvo branded ATF - Mobil 3309 does not seem to be available in South Africa).

[msir1995]

PieereC:

Keep us posted on using this T-IV. I am really leaning towards this since the software upgrade did not do that much. My fluid is brown according to the dealer. Also, this is interesting regarding the Aisin Warner transmissions, it seems Aisin Warner is a part of the Toyota Group, which may explain why I can get this fluid locally for $4.75 per quart. so, essentially, we have Toyota transmissions as do Ford 500 & Saturn Vue and Ion for certain years. Thanks.

[PierreC]

msir1995

Here is a selective extract from the Mobil 3309 product specifications brochure, which I picked up from some thread in this forum:

Product Description
Mobil ATF 3309 is an exceptionally high performance lubricant that meets original equipment manufacturers’ specifications for use in certain slip-controlled lock-up automatic transmissions. Mobil ATF 3309 is recommended for use in transmissions made by Aisin-Warner requiring a fluid approved against Type T-IV, JWS 3309, GM 9986195 and VW/Audi G-055-025-A2. These Aisin-Warner transmissions are used in CERTAIN domestic and foreign vehicles, including Toyota, Lexus, Audi, Saturn, Ford, Volvo, Volkswagen, Saab, Porsche and Mitsubishi.

Specifications and Approvals

MOBIL ATF 3309 meets the..........Model..................Part No. or Specification
following specifications

Lexus.......................................Most Models.........JWS 3309/TYpe T-IV

Volvo.......................................S60, S70, V70,......All 5-speed automatics
...............................................C70 , S80, XC90,
...............................................S40 , V40


I verified with the Toyota dealer that the transmission in the Lexus is in fact the same transmission as is used in the XC, and since Toyota spec for that transmission is the T-IV, and with the above Mobil spec as "confirmation", I decided to take the plunge and use the T-IV.

Maybe BoBoKwok, who had done a tranny flush wit T-IV quite a while ago can also give us feedback.

[JRL]

msir1995


I verified with the Toyota dealer that the transmission in the Lexus is in fact the same transmission as is used in the XC, and since Toyota spec for that transmission is the T-IV, and with the above Mobil spec as "confirmation", I decided to take the plunge and use the T-IV.


Not the "same" but very similar

[dtlayman]

Yesterday I purchased T-IV from our local Toyota dealer and today we took it to our independent Volvo mechanic for the transmission flush. Wish we would have done this sooner, but glad to now have it done at about 108,000 miles.

[BG60]

Just wanted to add my experience to this thread. I've been contemplating the transmission flush for some time now based on advice from this forum. So today I finally remembered to have my local Volvo mechanic check the condition of the fluid in my 01 XC70 with 94,000 miles. It was very dark and dirty. Needless to say I opted for the flush. I purchased the vehicle second hand in November 2005 with 59k miles and know nothing about its history except that it came from New York State. In regards to performance the only thing I've noticed is a hesitation when shifted from Park to Reverse. Not sure if this is normal or not because it has always done it.

This particular mechanic has 20+ years with the local Volvo/Subaru dealer and now runs his own shop. He has certificates of achievement hanging on the walls from both manufacturers. His business model is "if it ain't broke don't fix it.", which is why his customers love him and you can never find a parking spot at his garage.

His advice to me "was don't flush the transmission fluid unless it looks bad because of the expense ($157 for fluid + $37 labour)." My vote is to follow the advice I was given and ask the local shop to check the condition of the transmission fluid when the car is in for its regular oil change.

[v70+xc70]

I'm not convinced about flushing. A simple drain and refill of the fluid suffices for me. No pressure on the clutches seals etc. Coming up to 60k and another time to do a change.

[PierreC]

PierreC:

Keep us posted on using this T-IV. I am really leaning towards this since the software upgrade did not do that much. My fluid is brown according to the dealer. Also, this is interesting regarding the Aisin Warner transmissions, it seems Aisin Warner is a part of the Toyota Group, which may explain why I can get this fluid locally for $4.75 per quart. so, essentially, we have Toyota transmissions as do Ford 500 & Saturn Vue and Ion for certain years. Thanks.

As requested and promised, here is the feedback.

We have just returned from our [happy] summer holiday [happy] at the coast - remember, I am in the southern hemisphere - and have completed just more than 3000 miles since the transmission flush with T-IV fluid. About half these miles were travelled at highway speeds up to 80 mph with frequent overtaking and high-speed down/up-shifts and the rest in town, on mountain passes and similar shift-intensive driving.

The transmission did not miss a single shift, behaved "as new" and shifting is back to being extremely smooth, in all gear changes, up or down, when the transmission fluid is hot. When cold, there are occasions when the 1-2 and very infrequently the 2-3 shift can be felt, but in all instances it is not harsh or anything like a surge or "jerking" -- it is almost as if there is a very very slight delay [hundredth of a second - so slight that my wife does not pick it up at all] in the shifting, which disappears as soon as the fluid reaches normal operating temperature.

I will feed back after another 3000 miles or so, but at this stage it appears that the T-IV suits the transmission perfectly ... as expected. At the price, T-IV seems to be a good solution for the transmission flush.

[pelagikos]

For whatever it’s worth.

It was a while ago.
I was advised to replace the transmission fluid. Knowing that the service schedule does not call for it, I asked what's up with that. The guy seemed genuinely surprised and immediately resorted to BS, like "if your transmission goes, we will not honor the warranty... etc.".

I emailed Volvo. They replied that the fluid does not need to be replaced unless there is a specific reason for that like contamination, color, smell or transmission malfunction.

[Meat Popsicle]

Volvo of Richardson Texas refuses to flush transmissions. Where in Park City Volvo encourages it!

[goldxc70]

.... very slight delay [hundredth of a second ....

Just curious, how did you measure that? Are you sure it wasn't two one hundredths of a second :D

[PierreC]

Just curious, how did you measure that? Are you sure it wasn't two one hundredths of a second :D

... years and years of living in the fast lane where life's pace is measured in milliseconds ... so 1/100 th of a second is a long time!

Jokes aside, it was a manner of speech to signify a very very short, almost but not quite, imperceptable hessitation.

How would you have described it?

[goldxc70]

Yes, I was only joking!

To answer your question, I would say "slight hesitation" for what you describe. "Noticeable hesitation" would be longer and "definite hesitation" longer still. Ah, the beauty and lack of precision of the English language :)

[JRL]

How about all these trannies are slow shifting and call it a day :p

[PierreC]

How about all these trannies are slow shifting and call it a day :p

Its a day!