Hi all
After years of enjoying and caring for a 745T, I had to pass the buck to a more mechanically enclined owner (who has vowed to bring her to 300k and shows he will)… now I am discovering the XC70 (and, while enjoying modern aspects, believe it or not... regret certain features of the 740: turning circle, overall visibility, “sharper” brakes…).

I have an issue with the transmission I hope someone can relate to and help me remedy.
This well maintained 2003 car already has 186k highway miles, the transmission was never rebuilt nor flushed according to the previous sole owner. It shifts smoothly for about ½ hr of driving, after which the transition (up or down) from 1st to 2nd gear (as far as I can tell) can be very bumpy!

Any idea about what is causing this and how to cure? I am thinking of two possibilities: 1/ not enough ATF and as it warms up, becomes more fluid and there is not enough in the system for smooth shifting. Or rather… 2/ sludge which would progressively mix as the car gets driven and make these transitions so rough…
My mechanic (who is not a Volvo specialist) says these transmissions are sealed though, and is not keen to mess with it… but a quick search on the Board shows people do indeed “service them” (flush).
Would a “simple” topping off work? if the yellow “dipstick” is just a plug then, how to measure what’s needed?

Or should I talk my mechanic into doing a complete flush (he has a flush machine), if so, what would be the right amount of fresh ATF and best ATF brand/grade to use?

I was hoping to use this car for a long trip and would greatly appreciate any thoughts and suggestions from XC70 owners who have experienced the very same situation…

Thank you both for the detailed advice... The transm. was serviced with Mobil 3309 but... to no avail. It will have to be rebuilt; well the car has 187000 mi; I suppose if the previous (meticulous) owner hadn't driven mostly highway, this would have occured before. Any advice as to the frequency of servicing the tranny after this rebuilt (hoping that it will hold another 186k!)? every 50k?

First, get a second opinion and not at a 'transmission specialist'. Rather than getting it 'rebuilt', which is quite expensive, call Erievovo in NY state and ask for a used one. I would also ask if a 2004 tranny could be placed in your 2003, the 04 is better built.

The following from IPD which discusses the B4 servo cover:

Product Description
It's ironic how this inexpensive part can save someone from a costly transmission replacement.

The early AW55-50/51SN five speed automatic transmissions have an issue with shift “flares” and other odd symptoms related to shifting in and out of 3rd gear. Usually, this is exhibited by a “missed” shift (somtimes called "shift flare") from 2nd to 3rd gear on a random basis.

This B4 servo cover update can solve these symptoms in many cases. Other times, it may take a software update or the B4 problem has gone on too long and the transmission is physically damaged. It is possible for transmission damage to occur when the transmission hooks hard up after a flare condition.

Volvo has changed the design of the B4 servo cover multiple times and there are numerous Volvo service bulletins regarding it. The latest design is stock on later model years.

We highly recommend a transmission software upgrade prior to or in conjunction with the B4 servo cover update!

The software for these electronically controlled tramissions has gone though many version changes over the years and has become much more refined. A software upgrade can significatly reduce neutral to drive delays and shift flare. If your car still rolls backwards when in drive while facing up hill on a slight slope, then you most likely need a software upgrade. The neutral-at- a-stop while in Drive "feature" was removed with later software versions because it can cause damage when the transmission engages hard. Software upgrades must be done with a Volvo specialty shop using Volvo's VIDA application.

The B4 Servo issues usually don't affect 2004 and newer models, but some of these cars still have a variety of shifting issues that can be solved in many cases by a transmission software upgrade.
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My name is Klaus and I am a V ♂ lv ♂ holic

I hope that this thread was informative to other Forum members (or readers) with similar problems, I thank Klaus in particular for his specific advice.

In my particular case, to finish the story, the transmission problems were diagnosed at a local Lee Myles shop which was recommended to me by my mechanics. It took them some time as they wanted to rule out a few possibilities (needed to access dealer level diagnostics). At the end of the day the tranny had to be rebuilt, it was plain wear & tear ($2.8k incl. tax). They confirmed that it was the original tranny (which had held 186,000 mi, not bad for a 2003 XC70) and that it was Asian made (also in use on Nissan Maxima & some SAAB models). They recommend to service it from now on every 25-30k but asked me to bring the car again for a check after 500 mi-1k.
I read somewhere that a poster was intending to service his XC70 tranny every 50k, so to be on the safe side it might be a good idea to follow the advice of these tranny specialists and go every 25k. I'll let you know if the tranny holds another 186k...

Volvo has changed its mantra and now says that the ATF should be flushed at the first 100K mile and every 50K miles after that. Better than the old 'sealed system' so you buy a new car or tranny!

Still, never use a machine that flushes a tranny. Most of them operate at a pressure that is too high and can ruin internals. Flushing at home takes less than 45 minutes and is quite satisfying.

I am sorry you got the tranny rebuilt, actually that it costs so much! There is an internal filter that can get clogged with sludge and could have been the problem. This filter can only be cleaned after tranny disassembly - WHY have a filter if it can not be cleaned? Come on Aisin, think about all of us shade tree mechanics who would be happy to pull off the sump and replace an easy to get to screen.

Of course, when the tranny starts to shift 'hard', the damage is already done and the parts are worn to the point where they need to be replaced. I would still have contacted Erievovo and replaced with a used.

Klaus
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My name is Klaus and I am a V ♂ lv ♂ holic

The yellow dipstick under the intake piping is not a 'plug'. If it is, someone broke it and the metal part is now down in the sump (but, not to worry, it won't go anywhere). Removing the metal piece is not difficult, just take off the bolt holding the dipstick tube and pull off the tube, there is an O ring at the bottom. Remove the metal stick and put the tube back in place. Get a new dipstick.

You car must have 3309 ATF. The cheapest place to buy it is at a Toyota dealership. You will need 10-12 quarts to flush it.

Do not use a machine!! They typically have too much pressure and will break internals. Removal of the cooler hose from the radiator is much easier and you can do it at home in about 45 minutes or less.

I suggest that you first pull the plug for the tranny drain and let the sludge pour out, cold engine. That will be about 3.5 quarts. Then add new 3309 to the tranny through the dipstick (only place you can add it), equaling the amount taken out. Then drive for about 5 minutes with a few stop and goes to warm things up. Park the car on a level. With the engine still running, check the level on the hot side of the dipstick. Add 3309 as needed.

BTW, the tranny drain plug uses the same size crush washer as the oil drain plug.

Klaus
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My name is Klaus and I am a V ♂ lv ♂ holic

Does your car have a tranny dipstick? If so, check the fluid level first. Drive about 15-20 minutes to warm tranny. With the engine running, slowly move the tranny through all the gears when parked. Pull the stick and check if the fluid is within the proper range.

Do you know if the tranny's software is up to date? You might need to have it updated.

If it isn't the fluid or software then consider a flush. Assuming it is okay to flush a 2003 tranny, I'd first flush it thoroughly with a cheap fluid, empty it, and then replace with the correct ATF for your car. This should remove any sludge buildup that might affect shifting.