Drive Line
Transmission Issues
Transmission is the key weak point of this car. Lots of people have various problems with it ranging from minor to significant. But it really mostly come from
Bad software in the early models that was corrected later
Lack of fluid service schedule
Do these 2 things and the following additional low cost services will keep it running nice for a long long time. Of course, you have to start doing this early in the transmission's life, otherwise, too much damage may have been done.
Furthermore, diagnosing the exact problem seems quite difficult. Often, it is a little bit trial and error to go through all the typical problem areas. I get the sense from reading the forums most dealer service departments typically goes for the repair that guarantees the fix (replacing the transmission). But it is also the most expensive (~$4000 or more). I'd imagine if dealers do these smaller repairs first but doesn't fix the problem. They probably get unhappy customers.
I've compiled a list of low cost things to check if you are having tranny problems. These are much cheaper if you can do some simple do it yourself repairs. Nothing here is too difficult.
First of all, I should say I have only experienced the 3 following list transmission problems on my cars.
Wrong ATF fluid type. This cause transmission to shift funny
Gear 2 to 3 flare in manual shift mode on the geartronic transmission. What I have isn't too bad. Just take about 1 second or so before engaging into third when I go up hill. Other people report much worse including experiencing this in auto shift mode. BTW, nothing I did could fix this. I'm guessing I need a new valve body if I want to get rid of this minor issue on my car.
Broken lower transmission torque mount. This allows the transmission body to move around during shifting an can cause poor shifts.
So here are a check list for low cost remedies
If you have year 2001 or 2002, check your transmission serial number to see if you have a defectively design B4 servo cover. See here.
Check your lower transmission torque mount. See here.
Make sure you have the latest transmission software installed. See here. Might do the adaptation too (it will cost more). The adaptation (see here for more details) is basically a particular driving pattern that trains the transmission computer to shift as smooth as possible based on the current conditions in the transmission. It is possible to have dealer tech just turn on the adaptation mode and you go ahead and do the driving patterns yourself. If you can convince your dealer to do this, before to get the driving pattern directions. I'd do the adaptation after all above items are checked and/or corrected first.
Try some Seafoam Transtune to see if it improves. ipd guys seems to have tried it with good results. ipd TransTune product link
The transmission computer software can adapt its shifting parameters. It basically adapts the actuation of internal solenoids based your driving style and transmission's internal condition. To do the adaption, see here.
Install an external ATF cooler. Most transmission problems show up when the ATF is hot. A few people have noted surprisingly positive results with an external cooler. See here
I have done all these on both of my 01s. And other than the slight 2-3 flair in manual shift mode. My transmission runs fine at 132k miles and 116k miles. So I think it is worth it to do a little maintenance to avoid the big costs later.
Beyond this, you are probably looking at a valve body replacement (~$2000) or new transmission (~$5000). Here is the valvebody replacement direction (link)
A few thing to note before you undertake any of this effort.
Dealers service departments seems to be evolving away from doing these fixes and only promote the full transmission replacement. I'm guessing since none of the fixes above "guarantees" the fix. Dealer end up eating the cost if the fix doesn't work. This is obviously not a good business practice so I'm guessing they evolved away from this.
Before undertaking any of these fixes yourself. If you have full dealer service records and have warranty that expired within a year. Volvo regional and the dealer have been known to kick in some discounts on your transmission replacement. But if they know you had these service done DIY or a none Volvo dealer/independent repair, I wonder if they are less likely to offer the discount. Something to consider.
"New" Transmission
For those of you thinking about getting a replacement transmission from Volvo. You should know that the "new" transmission is not new. It is a rebuilt. And I've read a lot of people have problems with these rebuilts right after installation and some gradually turn in to significant shifting problems within a couple of years. I don't know the exact reason but it seems pretty clear that the rebuilts doesn't work as well as when these transmission were brand new.
After reading more about all the different moving parts for these modern transmissions, I've come to realize there is NO WAY to rebuild it properly without a huge amount of work and energy. There are so many moving parts and the cavity these moving parts slide in. There are lots of places that maybe worn. Can you imagine the rebuilder measuring the tolerances of all of these moving parts? I really doubt it. So unfortunately for us... there may not be any good solutions for us. Even replacement transmissions have may have worn parts from the very beginning.
Failing ABS and MAF can also cause poor shifts. I guess these units must also affect the transmission computer (through the engine computer) After replacing my failing ABS and MAF, transmission also shifted much smoother after a few days of adaptation. Failing MAF will give other symptoms such as rough idle, sputtering and random shutdown. Failing ABS will give errors such as ABS light.
Valve Body Replacement
Think you can do this job? If so, info here.
Adding External ATF Cooler
Most of the transmission problems tend to act up when the ATF is hot. Conventional wisdom suggest the thinner ATF when hot leaks through various wornout sealed valves. A few people have installed an external ATF cooler with surprisingly positive results. This doesn't seem to be a commonly known remedy so not much statistics at the time of this writing (1/2014). But I keep on coming across a few people that have tried it and got good results.
Here is a link to my experience.
How Do I Check ATF Level
I see this question asked here and there. And this car does hide the ATF stick pretty well.
You can see the transmission between the head/intake manifold and the air filter box. You will see a horizontal plastic tube feeding the underside of the intake manifold. Then there is a soft 1.5"? diameter tube running perpendicular below that. Radiator fluid goes in this tube. The ATF stick (yellow color) hides just beneath the intersection between these 2 parts. It is near the "front" (facing the radiator) of the transmission housing.
To check the fluid level, you need to roughly determine the ATF temperature. ATF takes a long time to heat up and requires 20min of driving or so. So even if your engine is hot, it doesn't mean the ATF is hot. Even after 20min, it is only about 80+ degrees C. By then, the engine will be very hot and the hot radiator tube is directly above the ATF stick making it difficult to access the ATF dip stick without burning your hand. One solution is to check the ATF level while the transmission is cold. You need to become familiar with the proper fluid level readings on the dip stick anyways.
ATF levels must be read while the engine is running. Just put the gear selector in every position (RND) for 3 seconds or so. Then return it to P and still leave the engine running. pull the ATF stick and check for the level. Keep your hand away from the electric fan mounted to the radiator. It could come on at any time.
Since the ATF is basically cold, just take the reading on the cold part of the dip stick. If you are adding fluids, make sure you don't add too much. 0.2L will result in quite of bit of movement on the stick. Here are a couple of links for your reference with a picture of the dip stick
http://www.volvoxc.com/forums/showpost.php?p=142862&postcount=9
http://www.volvoxc.com/forums/showpost.php?p=60224&postcount=9
TCM (Transmission Control Module) Software Update
The latst transmission software update is a significant improvement. It has a shift/lockup profile that allows the engine to stay in the good part of the torque curve more often (~2400 RPM for the T5). Consequently, the car is more responsive. Part Number for this update is 30677036. About $25 for the software and 1/2 hour labor.
My dealer service department told me is a chance this update may require transmission adaptation (I have never heard of this from other forum members). This adapatation is a 1.5 hour long procedure with varying driving pattern to teaches the transmission electronics how to shift smoothly. This would obviously cost more. My dealer service department said they can't predict if adaptation would be necessary before the TCM update. Luckily for me, it was not necessary. See here for more info on transmission adaptation.
This software update seems to be available sometime during 2004. From what I have read, early 2004s didn't receive this software during manufacturing.
It seems everyone is happy with this update. Especially the new shift profile.
I have both an 01 V70 T5 and 01 XC70. The improvement is very significant on the T5 and maybe only slight on the XC70. The T5 engine has a higher pressure turbo which takes longer to build up the pressure. This is the reason the good part of the torque band is above 2000 RPM. The new TCM software changes the shift profile to allow the T5's engine be in the good part of the torque band more often.
Transmission Adaptation
The automatic transmission can relearn how to shift smoothly based on the latest internal transmission conditions. Based on this, I'd imagine it is good to perform all of the other low cost updates (B4, lower torque mount, fluid flush, latest software) to the transmission first before doing this adaptation. I don't have any actual information that this order is the best. I just made a guess based on the purpose of the adaptation.
You need to have the VIDA/DICE diagnostic tool to set the transmission in adaptation mode. You can do this in the following way
Contact your local Volvo service garage (dealer or independent) and ask if they would just enable transmission adaptation mode for you while you perform your own adaptation drive cycles (1/2 hour). This is probably the easiest and lowest cost.
Ask the the garage to do the entire adaptation. They probably charge you an additional hour of labor.
Buy a Chinese made VIDA/DICE clone diagnostic tool and do it yourself. See here for more info.
Then you can use the following directions to perform the necessary drive cycles to have the transmission learn how to shift smoothly.
http://www.sonnax.com/tech-articles/TASC-TIP-07-08.pdf
I did this to both of my cars. Neither has significant shift problems but as strange as it may sounds, both had learned some bad habits from the past. Adaptation make both cars shift completely smooth again.
A good combination I found was
Add 1/2 can of Transtune
Drive it a couple of days
Do adapation
Shifts were pretty smooth after this sequence . YMMV on this transmission of course.
NOTE: An important note is transmission adaptation doesn't start until ATF reaches around 85C. The message window will show "Transmission Temperature High" when this temperature is reached. Until this happens, TCM won't be doing any learning and the warning triangle won't do any flashing to show it has learned any shifts.
Transmission Fluid Change
This car does not have a externally replaceable transmission filter. It is important to change transmission fluid even though Volvo has no recommendations. Given this transmission is the weak point of this car. I think you can't flush the fluid too often. Some people do 15k mile drain+fill and 30k mile flush. I think it might be good to do a 20k mile flushes to limit the wears on the solenoid valves.
*IMPORTANT* If the car has high mileage and you don't know ATF's replacement history. You might not want to do a flush. Flush loosens gunk in the transmission and circulate it around which can jam valves. Mechanics often recommend drain+fill (replace 1/2 of the fluid) follow by another drain+fill in a couple thousand miles. I haven't heard flush kills tranny for this car too often (did read a case the other day). I had a early 90s BMW, flushing those trannys at over 100k killed quite a few of those transmissions.
I flushed my ATF per directions below with Amsoil Universal Synthetic ATF. I had a lot of shift problems after. It appears to be not JWS3309 compatible (Note: the latest Amsoil ATF appears to be 3309 compatible. Just read the label). I then flush it with Mobil 3309 ATF and the shift quality is back to normal.
There are 2 low cost sources for ATF. The transmission is made by Aisin Warner (owned by Toyota). Toyota dealers carry the same identical 3309 compliant fluid for much cheaper than Volvo and common availability. It is identical to the Volvo fluid. Just Ask for Type IV transmission fluid from the Toyota dealer. It runs about $7-8 a quart.
Another source is the 3309 compliant Valvoline Maxlife. 1 gallon jugs are available at nearby Walmart for under $20.
http://www.volvoxc.com/forums/showthread.php?t=5668
http://www.volvoxc.com/forums/showthread.php?t=244
I do the following flush procedure which uses < 8 quarts of ATF and likely replaces 90%+
Drain and refill (about 3.5 quart)
Disconnect cooler return line and do 2 pump cycles. Each cycle pushes out about 2 quarts before aerating.
Remember to measure the ATF level, you have to use the following procedure. It is more than checking the dipstick with the engine off.
http://www.volvoxc.com/forums/showthread.php?t=7933
Fill From Dip Stick Hole ONLY
There seems to be a not so rare mistake where the repair shop would remove a particular bolt on this transmission to fill ATF. This kills third gear and require the transmission to be rebuilt or replaced ($4000+). So make sure you don't make this mistake. If you take the car to a none Volvo specific shop, make sure they know this. Here is one such horror story
More info here.
Remove Wrong Bolt To Fill Transmission Fluid
This seems like a common enough occurrence to warrant a caution. The transmission fluid on this transmission is filled through the transmission dip stick hole ONLY. But there seems to be quite a few non Volvo shops that removes a particular bolt to fill the fluid and kills the third gear on the transmission. Perhaps there is a wrong direction somewhere or a older Volvo's transmission that is different. Anyway, if you take it to a non Volvo specialist, print this out and tell them.
Picture of the wrong bolt to fill transmission fluid
Thread discussion on this topic
Fortunately, a Volvo tech figured how to repair this mistake without rebuilding the whole transmission. Post #69 and #70 of the previous link provides the necessary info on the repair.
B4 Servo Cover Replacement
A common problem with this transmission is the second to third or third to fourth gear shift flare. A shift flare is when the RPM "flares" up to about 3000+ RPM momentarily while the car is shifting between 2 gears.
One possible problem is a faulty design on the B4 servo cover. There is a washer that breaks loose causing shifting mechanisms to be imprecise. This part is only about $20 and requires probably 30 min to install. If you have the 2-3 or 3-4 shift flare, you might consider trying this. Volvo TSB claims only certain transmission serial numbers have this faulty design. The serial number is easily visible from the engine compartment. It is on a plate on top of the transmission. However, I have seen and also read about transmission SN beyond this range (all the way to 05?) which has the old more failure prone B4 servo cover design. So you might check it even if is beyond the SN range in the TSB. Here are the list transmissions SNs with this faulty design along with the replacement direction
http://www.volvoxc.com/resources/how-to/pdf/b4-servo-cover.pdf
Here is a tip if you were to replace your B4 servo cover. My old cover had 2 o-rings while the newly designed part came with 3. When I tried to put the new cover on with all 3 o-rings, it just wouldn't go in. It turns out the middle grove on the newly designed B4 cover isn't for an O-ring. The extra O-ring is the replace the ring on the "Piston". With the correct 2 O-rings on the cover and a new ring on the piston, the cover went in easily.
Additional directions and tips below
http://www.volvoxc.com/forums/showpost.php?p=74955&postcount=3
Angle Gear Fluid Leaks
On the XC70 AWD system, angle gear is basically the converts the horizontal drive shaft coming out of the transmission to the drive shaft going to the rear of the car. Its a 90 degree angle turn. Therefore, I guess they named it "angle gear".
Seems the seal facing the passenger side leaks quite often. The Volvo tech in the following link claims to have never seen one that didn't leak. If your car is still under warranty, ask them to check it on the next service.
http://www.volvoforums.com/m_105354/tm.htm
Its important to keep appropriate fluid levels in the angle gear. Given the frequent seal leak (but probably minor in most cases) here and having only 700mL of fluid in here, you might want to check the level during every oil change. To check the level, you can use any straight piece of tool (I used a straightened metal paper clip, a screw driver would probably work) and inserted in the oil filler hole at a downward angle to see if you get oil on the tip of the tool.
Common Misdiagnose
The turbo sits right above the angle gear and this turbo is well known of leaking where it joins with the air intake hose (PVC system dump some crankcase vapor into the intake and the oil vapor pools into oil puddles and leaks at this joint) This in turn drips right onto the angle gear. The following link suggest you might smell the fluid as angle gear fluid has a distinctive smell.
http://www.volvoxc.com/forums/showpost.php?p=130632&postcount=1
The turbo oil return line that goes into the oil pan is another common leak location and also sits just above the angle gear. So make sure you diagnose it properly.
In my V70XC, it is the common turbo leak that drops oil onto the angle gear. The angle gear has a tiny leak. In fact, I can not detect any noticeable fluid level changes 30k+ miles after I changed its fluid.
Here are the directions to change this fluid
http://www.volvoxc.com/resources/how-to/pdf/2001-v70xc-bevel_gear_oil_replacement.pdf
Caution: Note this direction calls for "Transmission Oil" in the parts list on the first page. This is NOT the ATF or Automatic Transmission Fluid. It is a much thicker gear oil than ATF. Proper substitutes are synthetic 75W-90 gear oils. The reason it is named "Transmission Oil" is because that is what Volvo prints on the bottle.
WARNING: DIYers changing oil often is a bit anal about getting ALL the old oil out. Since there are sharp metal edges in the gears inside the Angle Gear, the soft plastic tubing you insert inside can easily be cut. This requires disassembly to remove and turns a simple job into a much more expensive one. So just be happy you got most of it out and don't push/thread the tube inside too far. Here is an example of what can happen if you push your luck too far
Failing ABS Causing Hard Downshifts
See here
Complex Transmission
Modern automatic transmissions are very complicated. I have found a bunch of info on this AW55-50 transmission. From my research on the web, there are 2 main sections of the transmission. One is the actual gears system and the other is electronic solenoid and valve system called a valvebody that shift the gears.
A valve body basically works like this
Transmission computer (TCM) decides when to shift from a variety of information
TCM sends electrical pulse to the solenoids inside the valvebody. Solenoids are just mechanical parts that can move using electronically activated magnets.
Solenoid's movement controls the pressure of various fluid channels. This causes the gear assembly to shift.
A really rough summary but gives you some background to understand more.
A company called Sonnax provides new components to repair the valvebody. They are experts in this area and provide parts and educational materials for valvebody rebuilders.
http://thesis-treffen.de/phocadownload/technische-infos/PRE-ATRA08-RCW.pdf
http://avtopedia.ru/akpp/AW55-50 SN.doc
http://avtopedia.ru/akpp/AW55-50%20SN%20Transtec.pdf
Various Valvebody rebuilders have posted video showing how to clean and remanufacture these valvebodies
http://www.youtube.com/watch?v=rB5Mw8lGh7A
http://www.youtube.com/watch?v=H6F7_vPy2pg
There are even companies that produce improved aftermarket linear solenoids
https://www.youtube.com/watch?v=tUpHlpOlusw&list=PL24A173536EC8A59A
And directions on rebuilding the solenoids
https://www.youtube.com/watch?v=VVSS7NrHdZ8
I found the following valvebody rebuilders online. I've used ReamMan Valve Bodies, great price and good rebuild VBs. There seems to be more and more VB rebuilders come online so google around for the latest.
https://www.facebook.com/Ream-Man-Valve-Bodies-179252558759709/
http://www.valvebodybuilders.com
http://www.sunbeltvalvebodies.com
Omega machines seems to have some expertise for the gear portion of the transmission. Including typical casing and bushing wear.
http://www.omegamachine.com/db/Volvo-AW-55-50-SN-bushing.asp
Valve Body Replacement
If you are still having transmission shifting problems after the low cost + easy steps (lush the ATF, check the B4 servo cover, got the latest transmission software, and make sure the lower transmission mounts are good), you may consider replacing the valve body or at least the 3 linear solenoids.
Replacing valve body is a time consuming job. Therefore, the labor alone will be close to $1000 at most shops. But if you can DIY, there are 3 options
Remove the valve body and send it in for rebuild. Valvebody rebuild cost about $600 or so.
Remove the valve body and replace 3 linear solenoids. You can buy these solenoids in ebay. Just search for "AW55-50 solenoid"
Replaced the Valvebody with a GM equivalent that is much cheaper
Here is the valve body removal and installation direction
Here are some links on the success with linear solenoid replacement
http://volvoforums.com/forum/volvo-v70-13/transmission-shift-solution-aw-55-50-a-58714/
Here are a couple of links showing the weakness of the original linear solenoids and how they are rebuilt.
http://www.youtube.com/watch?v=qtiHATd5Q_c
http://www.rostratransmission.com/rostra-performance-class-linear-solenoids.php
Here is a link to someone who purchased a equivalent GM valvebody and adapted it for this Volvo
Notes
Here are my notes doing this job for the 2nd time.
Helped a friend replace a valvebody at 145k miles. Here are some notes on this job
Rebuilt Valvebody Source
I found a good priced source at reamman.com from a Volvo tech that used them several times with good results. At the time of this post (1/2015), price is $575 shipped including return shipping. Pretty good price.
Note they don't send you 2 new rubber seals, new bolts, and a gasket called for in the directions below. However, I think old rubber seal and bolts can just be reused and you can get full gasket kits online for cheaper than the single gasket from Volvo.
Directions
Here is a pretty good play by play direction. Valve Body Replacement
I found a couple of additional steps that make this job easier.
Remove the air pipe from intercooler to the throttle body (ETM)
This gives a lot more room to work with. For a nice trick on removing and installing this pipe, see page 9-11 (removing) and page 14 (installing) of this direction here.
Remove the aluminum plate below the air filter box
This is the plate that holds the feet/clip the air filter box sits on). This provides more room and also remove some sharp edges while doing the valvebody job.
Create more space between engine/transmission and subframe
You need to open up quite a bit of space between the transmission and subframe to get the valvebody cover off and on. It looks like it can come out easy but the cover has to move forward quite a bit to clear the valve body to come ou. To do this, I decided to remove both front subframe bolts. Use a jack with a wooden pad on the front of subframe if you worry the engine will drop out (it won't the torque bar you installed at the top will hold it nicely.
I also remove the 2 bolts holding the front engine mount (just below the crankshaft pulley on the passenger side) so the engine/transmission can separate further from the subframe to provide the necessary space. Note if the engine moves around a bit, these bolts might be hard to put back. I was off by about 1/8" and positioned a jack under the oil pan to gently push engine around a little until the bolts could be reinstalled.
Difficult to pull the connector on the 3 linear solenoids
I did this job twice, I was able to 3 connectors without damage to the solenoid's plastic connector housing once. 2nd time didn't have super thin screw drivers so busted the connector housing on the solenoids (old solenoids got sent back to the rebuilder for core charge anyway). Not really sure what is the trick to pull these 3 connectors but its a difficult step. Probably just need really thin screw drivers.
Have a helper when installing the valvebody and cover
Valvebody can be best positioned back in the transmission casing from below. However, there is a shifter linkage that needs to be attached at the top. A helper make this a lot easier.
The cover has very limited clearance to install and it will have uncured RTV gasket material around the edges that you definitely don't want to get on your valvebody. Practice putting the cover on without the RTV to get a good sense of how to get it in. A good way is to bring the cover in from top with a helper on the bottom of the car helping with aligning the lower cover.
When installing the cover with RTV, be sure to have a bolt handy to insert and hand tighten on top and bottom. The cover will feel tacky with RTV but since it is slightly tilted, the top will come loose without something holding it against the transmission casing.
CV Boot Clamp Leaking
Saw CV grease is escaping out of the CV boot past the clamp. I took a pair of side cutters and just tightened it down. No more leak :) Here is more info with pictures
Changing Rear Differential Fluid
http://www.volvoxc.com/forums/showthread.php?p=122255
Volvo's factory service manual says 01-02 fluid capacity approx 700mL. 03-07 is approx 650mL. Just fill until drip from fill hole and backout 100mL.
WARNING: DIYers changing oil often is a bit anal about getting ALL the old oil out. Since there are sharp metal edges in the gears inside the differential, the thin soft plastic tubing you insert inside can easily be cut. This requires disassembly to remove and turns a simple job into a much more expensive one. So just be happy you got most of it out and don't push/thread the tube inside too far.
Propeller Shaft Removal - Ping Sound Under Center Console
My 01 V70XC has a couple of "clicking" sounds when backing out and putting in D. Sometimes, there is a metal on metal ping from around under the center console. In my case, the ping noise occurred at a specific drive way where I entered at a certain speed/gear followed quickly by lifting the foot of the gas. The result is a quick shift in torque in the driveline that produces this ping noise. Took the center shaft (the drive shaft transferring power from front to rear of the car) out and both noises are gone.
This center shaft have 2 CV joints. One on each end. One connects to the angle gear while the other connects to either the Viscous Coupling or Haldex unit. In the middle of the shaft, there is a U joint and a bearing. Here are the pictures of the propeller shaft, CVs on each end, and the center bearing + U-Joint
I did see spun grease patterns around both the front CV joint (the end connected to the angle gear) and the U joint. Here are some pics I posted. I learned from prop shaft rebuilders that the hot catalytic convertor next to the this CV joint is the source of the problem. For 01+ cars, the CV boot is silicon and don't crack but the grease gets cooked by the cat's high temperature. <=00 cars have rubber boot and can crack due to this heat source.
http://www.volvoxc.com/forums/showpost.php?p=148342&postcount=1
This appears to be a very common problem on Volvo P2 AWD propeller shafts. According to a driveshaft rebuilder, XC90, XC70 and all AWD seems to suffer from this issue.
Driveshaft Removal
Here is Volvo's direction for removing the center shaft
A few notes on this job.
There is no need to remove the exhaust to remove the center shaft. But I imagine it would be easier with more room. But it looks like a lot of stuff to remove and I prefer not to mess with the seal between the exhaust segments. Exhaust can be lowered slightly. Just unhook the exhaust from the 2 rubber donuts just behind the rear differential. This gives a little more room to work on.
There are 6 6mm hex key bolts that connects each of the CV joints on either end of the shaft. People suggest you put the bolts back in the exact same hole. I just tape the bolts on a piece of card board and mark them 1-6 starting counter clock wise from where you indexed the shaft. There are also little curved washers behind each pair of bolts. I marked these properly as well so they can go back on the same location.
To remove the CV joint hex bolts, the car was put on 4 jack stands. Car put in D and I can rotate the tires to rotate the center shaft. Once I got to a desire location, I asked a helper to put on the emergency brake and step on the foot brake.
Becareful removing the CV joint hex bolts. It is hard to get the hex socket head on straight and you definitely don't want to strip these.
Unbolt the 4 bolts for the bracket that holds the center bearing. This gives more space for center bearing to bent and therefore shorten the shaft slightly for the CVs on both ends of the shaft to come off the flange they are mated to.
Unbolt the 2 center bearing bolts from the bracket.
Unbolt the bracket protecting the exhaust pipe in front of the viscous couple (01-02) or haldex (03-07)
Both ends of the driveshaft have a bumped extrusion on the CV joint (see picture above) that mates to the cupped surface on the input/output shaft they are attached to. This extrusion wouldn't clear the cupped face until I drop the center bearing low enough.
The CV joints can slide slightly so try to shorten the shaft by pulling the CV joint towards the center of the shaft. A little bit of rust may keep the CV joints frozen to the input/output shafts its mated to. You make need to break it loose with a rubber mallet and/or some rust remover.
Once the shaft is shortened slightly and the center bearing can bent enough to further shorten the shaft, it will come out.
Notes if the cars is driven on salted roads
The rear CV's cup fits in to the next stage's (Viscous Coupling or Haldex) input shaft flange and is held on by the 6 hex key bolts. However, I've read the cup face part of this CV's casing seems to rust on to this flange pretty solidly on cars in snow country climates. One member even split the CV's cup casing open while trying to get it out. One member suggest there is a hole on the flange to inject in PBlaster to remove this fitting. Mine came out with a good wack but I don't live in salted road environments. So just sharing what I've read. Here is link to this info
http://www.volvoxc.com/forums/showthread.php?22898-rear-prop-shaft-does-not-sllide-out
I believe the front CV separates fairly easily from the angle gear flange because it is in a more protective area and wet salty sprays travels only towards rear. The rear CV is pretty exposed.
Diagnosing the prop shaft
The front CV on the prop shaft didn't rotate smoothly on my shaft. And I can manually make it ping lightly by pulling/pushing the CV joint. The ping would be much louder with the torque in the drive train. So this is clearly the source of the "under the center console ping" problem. Colorado drive shaft (http://coloradodriveshaft.com/) will repair your drive shaft for about $450 shipped with core return. They also have a aftermarket CV source for much cheaper ($100-$120 on their store on ebay) than Volvo ($250-$300). At the time of this writing (11/2012), they had CV joint kits for <=2000 and >=2002 and soon will source 01-02s.
The spray pattern around the tunnel above the u-joint is likely okay. The u-joint on the prop shaft appears to be good.The spay pattern is probably just dirt collected by the u-joint and spun onto the tunnel.
On the CV joints, I believe the front and rear are the same. However, there are different part numbers on the P2s likely due to the change in AWD system (Viscous Coupling to Haldex)
01-02 is one PN
03-07 is one PN
<=00 is yet another model on the P1s
Spoke with the owner of coloradodriveshaft.com and they are really the expert on this drive shaft. He said the main problem is the nearby catalytic converter's high heat source. On the <=00 cars, Volvo used a rubber boot for this CV and it would crack under this high heat. This actually makes it easier to diagnose since you can visible see the crack. On >=01s, Volvo used a silicon boot and it doesn't crack but the grease inside the joint is ruined by this high heat source. Since the boot doesn't crack, it is a bit hard to diagnose. Anyhow, if you have an AWD and have that mysterious random ping sound when the driveline undergoes a less than smooth torque change. This might be your issue.
Here are all the components of a diassembled CV on this prop shaft.
The small opening end of the CV boots have either a positive ridge (<=2000) or a negative channel (>=2001). The end cap also have a little hole in center. These openings appears to enable excess grease and or air to escape. When the joint is assembled, a bead of CV grease came out of the end cap hole. This is not a problem as the centrifugal force will move grease away from these openings.
When tightening the new clamp around the boot, be sure to just tighten enough to prevent the boot from moving around. Tighten too much can damage the soft rubber boot.
Preventive maintenance on the front CV?
Read this
Rusted on CV joints
Some people have had quite a hard time removal rusted on CV joint in salted road areas. Here are some suggetions for loosening them
http://www.volvoxc.com/forums/showthread.php?28249-04-XC70-Propshaft-Removal
Oil Leaks on bottom of Viscous Coupler
The VC is sealed so the leak is likely due to a leak from rear differential pinion seal. Here is how to repair it
http://www.volvoxc.com/forums/showthread.php?21446-Rear-Differential-Pinion-Replacement
NOTE
01-02 has Viscous Coupler, rear differential filler hole faces the front of the car, oil capacity = 700mL. 03+ has Haldex, rear differential filler hole faces the rear of the car. oil capacity = 500mL (remove 100mL after oil start dripping from filler hole)