ULpilot

I couldn't find this in the search, if there is a thread, please just lead me to it.
Since I have had the car, I've had some problems which I am now guessing to be CV joint problems. The transmission really slammed into gear until I completely backed the modulator off. Now it shifts decently, but still forces a bit and makes a click-click sound whenever it shifts. The sound is a mix of a double click, tick, and pop sound (click your tongue from the roof of your mouth- that's the best decription that I can give).
I know the passenger's side boot is torn, it had been from the PO anyway. But it also sounds like the drivers side is bad and I'm hoping both aren't bad. Anyone know for sure what these symptoms are? Is there a way to test each CV joint, or look at it and tell it's bad? And I'm pretty sure, but I want to confirm- I can just replace the CV without replacing the axle, right? Lastly- I get that there's the cv joint bearing up at the transmission, but is there another joint that could be a problem down by the wheel? I hope not- it's pricey already
Thanks!

dr bob

Simon--

Inner joints can be replaced, outers are part of the half-shaft. There are rebuilt axle assemblies that have good joints on both ends if it gets that far.

-- Don't drive the car with torn boots.-- PO sold you a car with torn boots? Fix 'em before you drive it anywhere.

Your trans issue sounds like the vacuum line between the engine intake and the modulator is leaking or toast. test for engine vacuum at the modulator end with engine at idle. If no vacuum there, find and fix the leak. Then restore the previous modulator settings. With no vacuum, the trans thinks you have your foot hard in the throttle when it shifts, so extra-firm is the shift to protect the clutch packs from all the horsepower it thinks it's handling.

The CV joints often respond well to a good cleanout and repack with the right grease. I bought boot kits from 928 Int'l that included the grease and the clamps. the half-shafts come out with a minor amount of effort with a big bar and socket on the outer nut, and lesser effort with the allen sockets on the drive flange bolts at the inside end. With the half-shafts out, you can disassemble the inner joint form the shaft, pull both boots off, and wash all that old grease/dirt/muck out of the rollers and the cross. Paint thinner, after a through wipe-out with paper towels, will get it clean. Repack with the new grease in the kit. New boots go on, and the outer boot gets clamped. Inner joint goes on next, remembering which way the crosss was facing before you help it on to the shaft splines and put on the retainer clip. Fill that one with grease, add the cap on the end of the shaft that came with the kit, and clamp the boot. Clean it up and slide it back in the car. I think it's 60 lbs/ft on those inner bolts, 320-something on the axle shaft nuts.

ULpilot

Alright, I'm pulling it apart. But... HOW AM I SUPPOSED TO GET THOSE ALLEN BOLTS OFF? Is there any special tool I'm missing? Are these the ones that directly attach the axle/cv joint to the transmisison? There are many of them around the edge, right outside the boot on the transmission side. I've got an allen wrench that fits- it's about 3.5 inches long, and I can't get the torque to pull them off. Just want to make sure I'm not doing something wrong.... any tips are appreciated

Garth S

To remove the inner CV bolts, you need an 8mm allan socket: a 3/8" drive will do, but pick up a 1/2" drive too. Assure that the allan tip is fully in the bolt head before turning .... or you will be very sorry .
I reinstalled these at 47 ft.lbs torque.
BTW - you must rotate the axle to access each bolt - and lock on the handbrake each time to allow them to be torqued out.
You need some serious gear to remove the outer axle nut - a stout 28" long 1/2" drive has worked for me ( or impact tools). If you do mot have this type of gear, get a local shop to back off these 32mm nuts for you. Resnug just enough to get home - and dig in.

Bill Ball

You asked how to test the joints. Anyway, I assume you found the source before tearing it apart, so this is just for the record. I would have jacked the rear into the air via the rear crossmember, raising both wheels off the ground. Got underneath (after safely supporting on jackstands), grabbed one wheel and rotated it back and forth, listening for that click. If the origin was not clear, I would have used a mechanic's stethoscope to locate.

I have a click that eminates from the differrential. I'm pretty certain it's loose bearings on the small gears (removed the diff cover and could see the small gears rocking). My click isn't as prominent as yours, and it has remained the same for 3 years, so I am leaving it alone until I get ready to do a swap of the current open diff for an LSD.

dr bob

From the little tech spec book:

Rear axle nut -- Torque is 460Nm, translates to 339 lbs/ft
Drive shaft to transmission flange -- 81Nm, translates to 60 lbs/ft

As Garth suggests, that little Allen wrench isn't near the size tool you'll need. You'll also want to borrow or rent a torque wrench to get them tightened correctly when you are done. Several listers have reported critical failure when a half-shaft wasn't tightened correctly after service.

The nut on the wheel hub takes some serious effort to get loose, and deserves a shot with the torque wrench on reinstallation. Too much damage to be done if this isn't done right.

If you're not comfortable with this heavy-duty work, don't be afraid to take it to a professional. There's no particular 928 to this task beyond the grease and slime.

Garth S

Thanks for the correct data: I also concur on the dealing with the 'grease & slime' .
Recently, I swapped a set of non-ABS halfshafts into a '89 S4 for a few days - long enough for Jeff to have his slimey axels/ripped boots stripped elsewhere than in my grease pit. ( and only set the inners at 47 ft.lbs -- OK for that brief duration, but 60 ft.lbs is correct).

ULpilot

Sorry to be so elementary about this. I'm making myself feel like an idiot with all the obvious questions. I just don't want to mess up anything any more. Looking at the wheel end of it now, I need to take off the large (1 1/4in) nut that is in the center of the brake rotor/wheel? I need to get a socket that will fit this for my impact wrench (ok to use?) so I wanted to check the size. I 1 1/4in wrench fits on mostly, but is ther ea more precise metric size? And.... which way does it loosen. WSM says they are 'self-tightening'. Does this mean turn clockwise to loosen it? Thanks again for the input!

dr bob

They are both counter-clockwise to loosen, normal thread direction.

Your typical home 1/2" drive impact won't budge that nut. My 3/4" drive impact with 450 lbs/ft won't reliably remove it, so I go directly to the big 5' bar and the 3/4" drive socket. I don't remember the exact socket size, unfortunately. I have a set of 3/4" drive impact sockets and just grab the one that fits. Perhaps someone else will jump in with the correct socket size.


And don't worry about asking "obvious" questions. If it was really obvious, there wouldn't be a quastion. More than a few folks have figured how how to do a lot of damage, doing things that were "obvious". My wife is happy that I can get companies to pay me to teach them things that are "obvious" once they see how they really work. It's that transition between question and obvious where most damage is done. One of Fig Newtons other laws reminds us that "Good Sense Isn't Common!", and that "Good Education Let's You Learn From Experience... Of Others". Good sense says ask the question. Common sense and ignorance often involves crying. Why risk it when all you have to do is ask? Nothing to lose, everything to gain, etc.

SeanR

There are some great write ups on this page

http://members.rennlist.com/pirtle/keepers.html

Browse through until you find CV joinst, there are step by step instructions there, I used it as a guideline when I did mine.

Hope it helps.

jpitman2

The big nut is 32mm IIRC. I loosened mine with a jack under the socket bar - it just eases the tension off the nut smoothly against the weight of the car. When you run out of jack stroke, roll the car enough to load the bar back onto the lowered jack head, handbrake on, jack again. You can also get them tight enough to drive the same after re-assembly.
jp 83 Euro S AT 50k, BTDT

Bill Ball

Yeah 32mm is interchangeable with 1 1/4 inch. (32/25.4 = 1.26 = close enough)

1/2 inch breaker/socket will almost certainly snap. 3/4 equipment is needed. I got a set of 3/4 inch socket/ratchet from Harbor Frieght. Jumped on the end of the 20 inch ratchet a few times and it came loose.