960 Information

960 Valve and Head Problems. [Summary of tips from Tom Irwin] To avoid the sticking valve problem, which causes valve and piston collisions and consequent head meltdown, follow carefully this advice for 960 owners from Mr. Barrington of Barrington Engine of LA, rebuilders of many toasted 960 heads:
1. The Abe Crombie Tune-Up is a GOOD thing!
2. Put a fitting behind the AMM for occasional, brief WATER introduction to the Hot engine...while
running Shatters and blows away the carbon build-up.
3. ALWAYS ALWAYS use PURE SYNTHETIC OIL! VERY insistent on that one!

Leaking Cam Timing Sensor. [Query] The cam timing sensor on my 960 is leaking oil when the engine warms up. I have checked the location with a telescope mirror and is not from the seal around the block. Could it be an inside seal? [Response: Abe Crombie] There is a seal deeper in from cam sensor. It is a bear to reach. Go to dealer, they have a tool that presses it in. There is no room to tap it in with engine in car. The shutter wheel must be put back correctly also.

Porous 960 B6304 Blocks. [Tip on used car purchase: Kelvin Kean] We purchased a 92 960 station wagon in 1985 with about 30,000 miles from a Volvo dealer. In the summer of '98 the coolant started needed topping up about once a week. By October, it needed two quarts a week. After removing the exhaust manifold our mechanic found the leak, a line of pinholes in the side of the block. He attempted to seal the leaks using a compound often used by truckers to seal small radiator leaks. The fix lasted a week. From then until January, we used the car but had to add increasing quantities of coolant to the radiator. In January we took the car into our mechanic and went through five gallons of water keeping the radiator from boiling over. When the mechanic looked over the engine block again, oil was now bleeding from an identical line of pinholes on the same side of the block and parallel to the line of pinholes leaking coolant. The engine block is defective. There is no fix short of replacing the entire block, which means an entirely new or rebuilt engine. And this failure is a fundamental failure in manufacturing or design. It has nothing to do with the maintenance or care a car has received. No engine block should ever leak coolant or oil short of a million miles! We've contacted Volvo of North America and their position is that the warranty has expired and that besides we did not have the car serviced at an authorized Volvo dealer. We are now in the process of filing a formal complaint in court against Volvo and its dealer. Within the last month, our Volvo mechanic has had another 960 station wagon towed in that was leaking coolant even worse than ours. Volvo has also given that owner the run-around, but he did get a member of the staff of Volvo North America to admit that they had heard of "...four or five..." 960's having the same problem. [Response: Tim] Click and Clack the tappet brothers had a caller a few weeks ago with a similar problem. Seems there are problems sometimes with the castings on the 960 engine.

[Where They Fail: Tom Irwin] The 960 failures always occur directly beneath the exhaust manifold.

Early 960 B6304 Cautions. [Tip from Tom Irwin] The early run '92's, maybe 10,000 units worldwide had metallurgical and dimensional deviations. That was corrected quickly and all subsequent castings have been more or less to print [But see the update below!]. Having said that...let's address the coolant.
I have been told by reputable sources at Volvo that anything other than Volvo Blue, Type C coolant could begin to attack the block alloy with time. This reaction is accelerated as the coolant degrades. (Note, this applies to aluminum, modular engines, B6304, etc.) Naturally, if you have one of the early 92's this chemical reaction could damage the block faster. The same source also cautions against using anything but Volvo Brake Fluid due to the potential for reactive damage within the ABS pump.

[Update Notes from Tom Irwin: There are two TSBs addressing this issue, 221943 in March, 1997 and 221945 in June 1997. The one from March 97 was superceded by an internal document dated November 1998, that was a Service Bulletin, titled as a "troubleshooting procedure". Here is the BAD NEWS guys...it covers 960 from 1992 through 1994... they went cheap even at that stage and authorized only a block swap with some incidental parts...the original engine gut pack had to be swapped. They called it a "defect" and allowed 20.4 hours for the swap. [Further reference:] Internal Volvo Warranty Claim Documents address block casting porosity issues in one document as a 1992 ONLY issue. The
second internal document, Volvo tech paper 2120-001, covers block replacement, under warranty for 1993, 1994, and 1995+ 960's. This references block numbers 25000 to 52873.

[Finding the Block Number: Tom Irwin] Under the exhaust manifold in the webbed casting. Use a mirror and light. Or, Underhood, front body stretcher in front of radiator on your left. Riveted aluminum placard, Right column, top line, last 5 digits.

[Editor's Note: Too many reports of casting porosities in 92-95 B6304s have appeared on the Brickboard to dismiss these as related to a short run of early blocks. If you are considering buying a 92-95 960, do some serious investigating and take a hard look at the engine block for coolant leaks, patches, attempted repairs, service records, etc. to pin down whether the car has this problem.]

B6304 Compression Test. [Query:] Anyone know the correct procedure for disabling the electronic ignition and whatever else is required to check compression w/o damaging anything. [Response: Abe Crombie] There is a terminal in that electrical box on driver's side under hood. It is a single terminal that points up with nothing plugged to it. 12V will trigger starter. w/o key on and all coils and plugs removed and throttle opened while cranking you will safely, accurately get a comp test result that is valid. Warm engine also.

960 B6304 Intake Manifold Nut and Gasket Problems. [Tip from Jim Bowers] My '96 960 with 66K developed a rough idle last week. My friendly Volvo service mechanic suggested it was most likely a bad intake manifold gasket when I took it in to have the codes pulled. (I don't have a scanner yet.) So I armed myself with parts and this past week end I tore into it. I fashioned a diagnostic tool for pressurizing the intake system with 4 psi and the problem was easily confirmed to be the intake manifold gasket. When I took the manifold off I found several of the bolts to be less than finger tight!!! The gasket had sucked in and bulged out at the number 1 cylinder. The new Volvo gasket was of considerably higher quality construction than the old one so it may have survived even with loose bolts. However, I may have avoided the considerable project if I had tightened the bolts when I first got the car last summer at 58K! With that background I also pulled back the heat shield on the exhaust side and tightened the nuts on the exhaust manifold nuts as well. Most were still tight but 3 or 4 turned up some. One turned up a full half turn!

960 Fuel Filter Change. [Query:] Can someone outline the procedure for changing the fuel filter on a 1995 960. I plan to remove the fuel pump relay, run the car till it dies replace the filter, and put the relay back. Does that sound about right? I noticed what appears to be some sort of pressure relieve valve on the line in from the tank to the filter. Is this valve used when changing the filter? If so how? Also do I need a special tool for disconnecting the lines from the filter? [Response: JT Charger] Leave the fuel pump relay alone. After unbolting the fuel pump bracket, simply squeeze the rubber connectors back while holding the fuel lines. Its like connecting an airhose to an airgun, spring loaded, compression fitting. The other fitting you see in the fuel line is for us superstar technicians to check fuel pressure with. Leave it alone. Put rags under the old fuel filter before disconnecting the lines, to soak up the normal spillage, perhaps use a pan.

960 Automatic Transmission Questions. See the FAQ file for Auto Transmissions for more info.

960 Coolant Loss: Coolant Reservoir Cap at Fault. See link.

Timing Belt Changes. See 960 Timing Belt Change for important information regarding the timing belt change interval, which varies by model year for the 960 series.

960 Rear Cam Seal Repair. [Long, Involved Tale from Tom Irwin] First, many thanks go out to Steve, Abe and the other generous tipsters without who's help I would have had a bit more difficulty. .

OK, the heater hoses are in the way so in preparing to disconnect and remove them I drained ~6 litres of coolant from the petcock on the Ex. side of the block. Make sure you have a jug of Type C Blue sitting around before you start, if you choose to do it this way. Well, then I noticed that with the coolant drained, the hoses became soft and flexible enough to be squished back/down out of the way. So I did that and left them connected.

Don't even think of doing this job without a telescoping inspection mirror, preferably a self-illuminated one.

The 2 T-40's that hold the cam sensor housing to the head...these are BIG mamajama's! They are made of soft metal and are easily deformed. And I promise you, they are frozen in their threads. Breakaway torque is considerably stonger then the set torque values. **CAUTION** if you strip or otherwise wreck the bottom T-40 fastener, you will likely have to PULL THE ENGINE to complete the job...'Nuff said.

Also, DO NOT use an El Cheapo T-40 driver bit either...if it comes out of a kit with a bazillion other parts...uses different adapters to connect it to a plastic handle and says "made in China"...GET THEM OUT OF THE WORK AREA..
Luckily, I went after the top T-40 first and the bit yielded under load and wrecked the head of the T-40!! Because it was the TOP one I was able to grab it hard with a monster vise-grip and bust it loose, after which it spun right out, no problem. My wife went out and got me a hardened, impact grade T-40 x 3/8" ratchet drive bit. Made ALL the difference! Even after I cheezed up the lower one a little, this quality bit grabbed it's target and brought the lower bolt out.

The Cam Sensor cover may be a bit gummed up with oil residue, so it may want to rotate a bit instead of withdrawing from the head. Fine! Rotate it CCW a bit and you can tap the upper and lower mtg. ears with a drift and light hammer alternately, until it walk's out. Set this aside.

Remove the 10mm bolt that retains the "shutter wheel" this is kinda like taking out a rotor from a distributor housing. no problem. Set the shutter aside. Wipe out the pooled oil.

If you are smart you'll have a seal picker kit with many different parts to make many different articulated angles...you will need them. If you are *me* you'll waste an hour sacrifice two craftsman screwdrivers in a vise with an Acetylene torch, trying to fabricate the same thing. For the record, the smaller one worked better. Use a Dremel tool or equiv. to de-burr and hone the business end of this thing so as to not damgage any sealing surfaces.

Now is when you MUST have an inspection mirror. Get on back there, work carefully as you are working a mirrored image. Hook that sucker under the garter spring + up behind the metal ring and it pops right out real easy. Wipe the cavity out again and reinspect the sealing surfaces for damage.

Lube up the new seal with... I dunno...I used heavy weight petrolatum..and ease it over the cam shaft. Try and jam several fingers back there and push evenly on different point on the seal. Make sure it doesn't cock in the bore. Stop and use your inspection mirror frequently to check it is even. To bring it home...again, if your smart, you'll find a way to get a hold of Volvo Tool P/N 999-5450. It has a perfectly dimensioned steel cup with a hole in the back to put your cam shaft shuter bolt thru temporarily to tighten the cup down and push the seal in to place. If you are me, you'll hack a piece of nylon bar stock at work and while the prototype machinists are on break and "borrow" a CNC Vertical Mill and fabricate same based on Seal dimensions and your best guess from a picture in the service manual.
Anyway, my best guess was about .250" off, but before I ran off to get a longer bolt, I put both hands on it and squeezed it against the head and ... "Whump" it popped right in. Check it again with the mirror for even seating.

Put the shutter + 10mm bolt back in. Fit the tabs squarely in the milled slot on the end of the cam. Tighten.
Clean the rim on the sensor cover and gently fit it over the shutter wheel being careful not to damage
the magnetic pick up chingas inside. Align the holes and replace the T-40's.

Fill-up your coolant. Take a Prozac. Start your engine. Check your work.

960 B6304 Cam Gear Timing. [Query: JT] I removed the cam gears from the head of my 960 and now can't figure out how to get the gears back on with correct alignment so the cams and valves are timed right.
[Tip: Tom Irwin] Make sure and scribe the bolt positions on the gears before removal. There is an awful lot of adjustment in there.
[Self-Diagnosis: JT] I took a look at the 960 again last night and I cam up with a way to solve the problem. The problem was that I took the cam gear off of the camshaft and did not know that it was not pinned or marked. This meant that it could go on the camshaft one of 3 ways at 120 degrees out of phase. With the intake manifold and exhaust manifold off I could see the valves. Had to use a mirror for the exhaust side. The spark plugs were out also. I set the timing marks and hoped for the best with a 1 in 3 chance of getting it right. I did not get any interference when I slowly turned the crank by hand, so feel will not work. I checked the firing order and compared the exhaust valves openings to the intake. Used a flashlight to shine in the plug holes and look in the ports to see when the valves would open. I found that the cam gear was off, making the intake and exhaust valves open and close at the same time. This is why there was no interference. So the intake valves were opening to soon. So I went back 120 degrees to the next hole and retested. This time the timing was correct. I then marked the cam gear to the camshaft so I would not have this problem again. So all you 960 owners out there be careful with the cam gears. I do not know but the 850s may be the same way.
[Response and Caution: Jim Bowers] The Volvo tools to set the cams cost about $250. There is a tool for locking the crankshaft in position, about $50, and one that attaches to the back ends of the cams, almost $200, and puts everything in sync. In addition to the three possible choices with the holes in the gear/pulley, the holes are elongated so you still have several degrees of choice once you get the correct holes lined up. The car will probably run, but will not be set at factory settings if you don't use the tools. Maybe you can find a place to borrow the tools? Or, once you have it in running condition get to a dealer and have the timing set. I just ordered a set from Kent-Moore, the Volvo tool supplier. Same tools are used for the 850 and probably for the S40? All that having been said, you would have saved your self a lot of hassel if you had spent the few $ to get the Volvo Service manuals for the engine. One of the books I have (TP31714/2) takes you, in pretty good detail, through changing a head gasket.
[Tip from Tom Irwin:] I've heard the following is critical to re-assembling the head: bottle of gasket goo, rollers and tension spreaders? The stuff I have is "Volvo #1161059-3, High Temperature, Chemical Gasket", it comes in a 50ml tube.

960 B6304 Leaking Rear Main Seal. [Query:] It appears the rear oil seal is leaking on moms 95 960 65k. This appeared all at once. It seems to be coming down from the flywheel ispection cover. I cant identify a drip while running but it pools while sitting. She just had the oil changed then this happened. [Tip from Rob Bareiss] The reason for the sudden blow out is... it's the same rear main seal as an 850 engine. Which is to say, subject to unexplained and sudden oily failure. I dunno, I can't really adequately explain it. They just let go, it seems completely at random. We've just done our 5th 960 rear main seal in the last 6 months, and I don't even want to think how many leaky 850 rear mains we've seen- it's gotta be 30 in the last year. At the minimum. I had 4 850's we sold this summer, everything from 48K to 114K miles, and we bought the cars because they were blessedly dry at the engine/trans split... and they came back, from 1-week to 2-months later, well within our warranty period (lucky us!) having sprung leaks. And I've had 150K mile 850's and 960's which have never leaked. I do not understand it, or know of a fix or cure for it. I'm sorry it happened to you- hope it doesn't dim your opinion of an otherwise great car. If you were to bring it to my shop, you'd be looking at ~$21 for the part, and about 6.5 hours labor. And, be glad that went instead of the catalytic converter....

960 B6304 Oil Pressure Problem: O-Ring Problems. See link.

960 Oil Pressure Problems: Failing Oil Relief Piston. [Tip from JT] As you know I have had some problems with no oil psi after I got the 2.9l back together. I thought that the oil pick-up was plugged with sludge or something. I know I did not want to drop that oil pan so I figured that I had nothing to lose by trying to clean the sump. I put in 6 quarts of the gunk parts cleaner (comes in 3 qt cans) thru the dipstick hole and let it set for 2 days. When I drain it the oil sump was spic & span! I flushed it with oil, then tranny oil, and then with oil again. I then filled two caulking tubes with mobil-1 0w-30 oil and with a rubber stop (with a center hole) pressurized the oil system thru oil filter inlet. I put the filter on, filled the sump with oil, and cranked the engine. No oil psi! I had to know what the heck was going on with this no oil psi. Still not wanting to drop the pan I went after the new oil pump. When I got the pump off it did not look right to me. What I thought should be the oil psi relief valve looked strange. Never seeing one of these before in the new Volvo engines I was not sure how it was suppose to work. What I found was a cylinder in a cylinder with a spring going thru it. I went to Volvo and ordered everything I could (except the pump) that was associated with the pump. It was clear when I got the new parts. The inside cylinder used to be a piston. The wire snapring chipped away at the piston top everytime it would hit the stop. Since the relief valve is made out of PLASTIC with the force of the spring behind the piston top, it was

chipped away until the spring blew the top on the piston off! No oil psi. The new piston is made out of steel. So this will not happen again. This was a new oil pump that had this plastic piston in it. I am told that the 850's use the same pumps. My sisters 850's oil pump took the big vacation about 2 years ago and I wonder if this was the cause. The casting date stamp on the oil pump in the 960 with the plastic piston was 98. So formational purposes, the next time you do a timing belt, you may want to check to make sure you do not have a plastic piston relief valve.
Techniques: [From JT] The good news is that you do not have to take the oil pan off to check/replace the relief valve piston. I never took my pan off. I am really happy that I did nót have to take that step. I do not know how many oil pumps came with plastic pistons or when there was a change to metal ones, but I say rather safe than sorry. If you are coming up on a timing belt change, pull the crank pulley and the crank timing belt gear. You will see four Torx head bolts that hold the oil pump in. Remove the bolts and the pump slides straight out. The piston was about $12 and the oil pump kit was about $23 (including front seal, oil pump seal, oil pump gasket). If you have a plastic piston in the relief valve you will have to separate the oil pump by removing the back gasket and removing 2 small hex head screws. Push the piston out and put the new one in. That's all. When you get ready to install the oil pump back into the engine you will need a special tool to get the front seal over the crankshaft. I used a thin walled piece of pipe but I think the book called for Volvo tool #5455. It makes the job real easy to get the oil pump back on.

960 Engine Won't Start: Sticking Valves. [Query:] We have had two instances of sticking valves preventing the engine in our 960 to start in the past two years. This has caused the engine to flood, fouled plugs, and with several attempts to start, gas in the oil. It is getting expensive at $500 a pop to "fix". Our dealership recommended several things:
   Changing to synthetic oil
   Rinsing the engine with a Blistein cleansing/filtering system
They also stated that these cars were meant to be driven hard (o.k.), as on the autobahn (Montana here we come!). So I guess my wife will have to become a bit more agressive on the trips to the grocery store... What gives? [Editor's Note: see 960 Valve and Head Problems above.]
Abe Crombie Tuneup Solution:
    The 4 valve/cylinder engines use small valves and the accompanying lighter valve springs. The exhaust valves will on any engine get some accumulation of deposits, primarily from fuel combustion with some portion from oil that seeps through guides for valve stem lubrication, that in some situations can cause the valve to slightly bind in guide. On a cold engine the guide-valve clearances are reduced due to temperature and the fact the metals of guide and cyl head shrink more than the metal of valve stem. You attempt to start engine and the oil system can and does build oil pressure on these engines in one crank revolution. This leads to the hydraulic valve lash adjusters ("lifters") filling and extending ("pumping up") while the sticky valve is closing sluggishly and not following the cam profile.
    A strong contributing factor is excessive fuel system cleaning additives. I know this flies in the face of what has been said loudly and often for the last few years but it is the truth according to a recent study on this very no-start, low compression problem. The additives used for fuel system cleaning make the deposits on exh valve stems worse. If you don't have a fuel system problem with symptoms then don't add anything to tank in the form of a cleaning additive.
    Premium fuel has lower volatility and is harder to ignite in cold weather. This can make engine not fire as strongly on initial cranking and less than stellar starting performance give the "lifter" pump-up problem time to occur. If the engine fires off and reaches speeds over 600 RPM the lifter filling time is lessened enough to diminish the odds of the pump-up. Cold weather also reduces the need for higher octane anyway as spark knock is less likely in colder air temps.
    Regular operation of the engine at eng speeds over 4500 RPM for 5 minutes or more will cause valve rotation that will clean stems of valves somewhat. This can be done by driving with cruise set in "L" position on gear selector at 55 MPH. THIS WILL NEVER HURT THE ENGINE! QUITE THE CONTRARY, IF YOU DO THIS, I GUARANTEE YOU WILL NOTICE A SMOOTHER IDLE WHEN YOU STOP AFTER THIS EXERCISE OF ENGINE!!! I was amazed at the difference when I tried this on my parents' 95 960.
    If the no compression, no start condition occurs you can usually get it to start if you will keep your foot on throttle 1/4 open and operate starter for 30 seconds at a time with a 1 minute rest. Keep throttle open until it starts. If 6 attempts (3 minutes starter time) have been made and it is not running then you will have to have a tow to a service shop. If cranking speed becomes slow during this time indicating you have a severely weakened battery, stop and charge battery or give in and have it towed to service shop.

[TSB Reminder from Jim] Volvo TSB #TP 31714/2 "Deposits on Exhaust Valve Stems"
"M/Y 1992 960's [dated 8/93] which are subject to driving conditions consisting of short, low speed trips may experience reduced performance or vibration as the engine warms up. Another possible symptom may be a sensation that the transmission lock-up is engaging and disengaging. In most cases, this is caused by sticking exhaust valves due to deposits on the exhaust valve stems. This condition, in most cases, can be solved by replacing the engine oil with synthetic oil (see Service Manager Bulletin 22-3) and driving the car at a high RPM (5000-6000 RPM) for 12 minutes in low gear. This test drive will remove the deposits from the exhaust valve stems. The synthetic oil will help prevent new deposits from being formed on the exhaust valve stems." [Editor's Note: probably applies to every B6304 ever made, not just model year 1992.]

If Your Car Has Had This Problem: Check Exhaust Manifold Pipes. [Tip from victim Tom Irwin] As a result of a sticking exhaust valve, the exhaust pipe broke, internally, just inches below the cylinder head. The resulting backwash of resonating exhaust caused symptoms of lost performance/compression. Symptoms of break: radial cracks around the pipe.

960 Engine Stalls and Won’t Restart: Wiring Harness. [Query from Tom Irwin:] I stranded in 100 degree heat. Got the car 4 blocks to home (thanks Triple A). Ran the codes and came up with DTC's 113 and 115. This points to Injector groups 1 and 2. Twice before, only 113 came up. I've done everything I reasonably can. Checking all connections and ohm specs. I greased the 55pin connector at the ECM. [Response: Abe Crombie] Check the wiring harness on engine where it comes up through intake. It may have rubbed through and grounded to engine. [Findings from Tom:] I checked it out, right there between the # 4 and 5 intake runners. About a .750"d loom. Had just enough clearance to sneak in a bentnose plier and move it around. The loom cracked away like egg shells. I could not see the rub point on the wires, but right at the head casting extrusion was a bright, shiny, rub spot. I pulled the loom/harness away from the head. And BOOM! Christine sprang to life. This makes total sense. It has always died upon acceleration. The torsional moment of the engine would tend to bite into anything against it. I lost only group one the first time because only one wire was worn through. With time, two wires, thus both groups lost.

Painted Bumper Cover Repair. See Painted Bumper Cover Repair for more information.

960 Driveline Noise: Failing Grease Seal at Rear of Driveshaft. [The Tom Irwin Chronicles, Ch 47: Tom finds a "tink-tink" sound coming from somewhere under the 1995 960. After repairing a cracked exhaust manifold, he starts examining the drive shaft and multi-link suspension.]
Continued: THEN, at THE VERY END OF THE DRIVESHAFT, just before it mates to the Rear end... I push up and down on it..... "TINK-A TINK-A TINK-A TINK"... and it moves a bit... That's "TINK-A TINK" under ONE 'HAND POWER'... start applying HORSEPOWER to it and the sound might EASILY sound like what I'm getting.... YES, this is it... Now... WHAT's Going on??? This driveshaft end looks different from the book, it tapers down from a tube to a solid rod, then it terminates at a LOBRO-looking joint with 6 or 8 HEX Screws and a few shims... it's only when in motion, or rather under acceleration.. REALLY LOUD "TINK-A TINK-A" noise. Like an exhaust pipe... But I just replaced EVERYTHING North of the Resonator... This end of the driveshaft SEEMS to be a tube welded around a shaft rod, like a modified Constant Velocity Joint, with a rubber boot and the works..?? What's inside the cadmium-plated cap? A Bearing/Bushing? Did something possibly break in there? Do you just need to re-pack the grease sometimes? There is a LARGE AMOUNT of dried, caked grease all over all around this thing and the gas tank tunnel where that bugger sticks out... Looks like it has been SLOWLY losing a bit of grease every so often over 5 year and 125k miles. The boot looks ok... probably out of the end cap... I'll use the RTV.. Interestingly the spray pattern of the grease is fairly widespread, fore and aft span totals about 18 inches. I'll bet tomorrow I'll find it dry as a bone... hope there is no galling or pitting of the balls. THIS appears to be the cause of the "TINK-A TINK-A TINK-A" sound, previously blamed fully on the broken cat pipe..... That little burp up to 6,200 RPM dropped me crisply into 1st gear and must have WAILED the shit out of that shaft, displacing enough grease to allow the bearing to slap. The noise of course would be amplified by yet ANOTHER STEEL sleeve tube over an inner pipe/shaft...
[Comments from Abe Crombie] The end of the shaft is welded to a splined shaft to accept the joint. It is a CV joint with the inner 6 slot hub driving the outer 6 slot housing via 6 10mm +/- ball bearings. The grease can dry out and the joint will wear a bit and the driveshaft will actually begin to move axially and make noises. If you are lucky the grease will fix it indefinitely. Does the grease deposit line up with the CV joint-pinion flange joint or does it look like it escaped through the boot? The boot on those should last almost forever unless road crap maybe damages it. If it looks like it seeped through the cap then seal it with silicone sealer on outer perimeter to prevent this loss of lube again.
You can remove rear section of shaft from pinion flange via the 6 Allen bolts. Tap the end cap off the joint. Once the shaft is removed at rear you will see the back end of this joint is closed by a cadmium-plated cap. You should be able to tap around the edge of the cap and get it off. Wipe out the grease and then pack it full of wheel bearing grease and then place cap on and reinstall shaft on pinion flange. Oh, BTW if it's not too late you should mark the joint to the flange to preserve balance if it was dynamic balanced. It will be paint-marked if the paint has lived this long.
These assemblies have no history of failure so piece service parts aren't available. The whole shaft would need to be replaced. The CV-jointed rwd driveshafts like this are rarely serviced on any of the Euro (Volvo,Benz, or BMW) models.
[Comment on Grease from Jim Bowers] I believe the grease for CV joints is something more than axle grease. Years ago, I used to get some special stuff from the dealer for the CV joints on the axles of my Porsche. It looked like it was loaded with Molybdenum Disulfide. Anyway, I think the parts store should have something recommended specifically for CV joints.

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