e9stibi

All -

I had the sensation of a ball joint failure (front control arm to wheel carrier on passenger side) during a drivers education event. The threaded stud broke under cornering load and it popped from the wheel carrier. Fortunately, I did not hit anything and my track buddies did not hit me while being stranded on track out of a very fast corner.

However, it is a pretty nasty failure of a relatively inexpensive part because the car could not be moved with wheel installed. If I only had a spare part but you know how this is Saturday at 12:30 PM ...

After the flat bed got me and the car home, I could assess the damage today.

Beside the ball joint, I need to replace the drop link because the boot that connects to the carrier is completely torn and the fender liner that got harassed.

Now to the point where I do not have experience and I would like to get your input:

Due to the movement of the passenger side suspension, the axle popped out of the differential and the transmission oil went out through the seal opening . You can see the joint flange in the picture with the snap ring. Can I just "pop in" the complete axle with joint flange. When tried to push it in, there was resistance which should make sense because the flange must be pressed in there somehow.

How do you recommend to put it back together and which items do you suggest to replace? Thanks for all your help as always.

I would like to get the car into a state that I can either drive it to my shop for thorough inspection and alignment or at least drive it on a regular trailer.

Garth S

Separate the center diff stub axle from the halfshaft ----- note the spring clip on the stub axle: it is the spring clip that locks the stub into the diff, and it requires a fair smack with a heavy hammer to drive it home ..... a 2.5 ft length of 1x3 0r 2x4 is an adequate driver, as .... well, read my old post on the deal front diff output seal/stub axle service Factory procedures call for replacing the spring clip - I'm 50/50 on using a new clip - never had an old one pull out in service.

As your stub left rather violently, it may be wise to R&R the seal .... the same wood drift serves to set the seal also.

If the seal does leak, run long M8's through the stub's flange to contact the case - and 'press' the stub out.

e9stibi

Garth - thanks a lot for quick response. I will replace the seal just to be sure. Because the seal did not leak, I will leave it alone or should I address "while in there"? What is a good tool to pull the seal.

Looks like I should be able to do this in my garage which is good news. The rest of the suspension looks ok but I will see when I put it back together and have it checked by another set of eyes.

I have the front end lifted and should be ok to tighten the suspension bolts while lifted. I have an RS adjustable sway bar. Please confirm.

Thanks again for quick help.

Garth S

No huge risk to go with the existing seal - leave the plastic cover off for a few days to see if it leaks: even if it leaks a bit, diff lube is cheap, so in the worst case, top it off until you have time to address it ( that's why I had noted the use of long M8's to press the stub from the diff.

IIRC, a flat blade screwdriver can be used to flip the seal out ( by catching the inner lip of the 'tin' - use a small wood block to protect the diff case when prying. Alternatively, a small size 'lady slipper' pry bar will capture the seal lip to flip it out ..... if it resists, with screwdriver & hammer, tap the outer edge of the seal's can inwards ( radially) to collapse it a bit.

As far as resetting subframe bolts, I always slide a separate floor jack under the hub carrier/knuckle, and jack upwards until the chassis starts to unload from the hoist ( or jack stands) ..... that approximates a loaded suspension at static ride height, and works for me . This may not be needed for subframe bolt retorquing, but in general, is the trick (IMHO) for all links/control arms/etc.

NYC993

Glad this ended up being relatively harmless. That ball joint is on my list to replace when I redo LCA bushings.

Just take the AWD out!

e9stibi

I was thinking about this but at the end I would like to be able to put the car back to stock.

e9stibi

Garth - more Qs that I rather ask here vs. PM to document for others in the future:

1. The manual asks for lubricating the seal with Liqui Moly Pu 53 or similar. I could not find this stuff online. What is the recommended grease and where can I buy?

2. When I disconnect the axle from the axle flange by removing the pan head screws, do I need to worry about the CV joint "falling apart". The manual recommends the use of to 8mm bolts and nuts to keep it together. Any guidance on this?

3. Do I need to grease any other spot before putting the flange and the axle in?

Thanks again for getting me though a part of the car I have not touched in the past.

bcameron59

Just be warned, I did this job (to refresh seals and front diff oil) per Garth's excellent thread. For some reason, it was the toughest DIY I have done yet.

Top of end rebuild? Easy peasy. The infamous spark plug by steering pump? No problem. Suspension rebuild, with front control arm bushing replacement? Meh.

Doing this one, on your back with 18" clearance? Now THAT was tough. Gave me some real respect for Garth, I can tell you.

Garth S

Hey guys - back again, pls excuse a slow response: as I'm down to a 928 & Cayenne , I do not drop by as frequently as in the past - but I still have the addiction.

Ok, to lube a seal, I've used any good bearing grease and wiped a thin bead in the back side of the tin (can) ..... covering the coil of spring that tensions the seal lip. In this case, as 75W-80 GL-5 is the diff lube, it can also do the job, plus wipe down the splines on the stub axle: while all of this is to assure adequate start-up lube, a primary reason is to avoid nicking the seals lip with the splines on insertion. Additionally, spin the axles/diff after assembly, and the diff gears will distribute the lube.

Don't worry about finding that particular grease .... do use a top GL-5 in the diff ( I use a lubri-Moly product, but there are several great choices.

The inner CV joint is enclosed on the stub contact face by a pressed on (bronze colour) tin - it is a @#%&$ to pull off at the best of times, so I would not worry about the CV parts spilling out. Also, the inner CV boot is clamped to both the half shaft & CV - not a primary concern for spilling its innards ....

As far as pre lube, that should cover it; the only caution is to clean out the seal's well in the housing, and get the seal started square to the case .... it is an awkward spot to in which work, but that step deserves the time to avoid messing up the seal. Once its straight, use a drift to seat it flush.

I have never fully removed a front diff, but have had one fully disconnected when replacing a torque tube/central shaft .... you can get a surprising amount of 'wiggle' room for the diff by doing this; however, there is a lot of grief involved in getting there - confident that you do not need to unbolt the diff /chassis mount.

Cheers,
G

e9stibi

Garth - thanks for additional input. I am still getting all the parts together and it would be good news if I am not coming back to you ...

Just to confirm, you use the high quality bearing grease to lubricate the inside of the seal (this is stated in the manual) that touches the shaft and either use the same stuff of GL5 gear lube to lube the outside of the seal (or the tin) to help it moving straight inside.

Another confirmation is that when I remove the pan head screws that I can take off the axle flange without the other side that sits on the axle falling apart.

Thanks again.

Garth S

Hope that clarifies ...

e9stibi

Garth - thanks a lot again.

Any specific recommendation on what what to use for the greasing of the seal? You mentioned a bearing grease.

Upon further inspection, I found out that the seal is damaged and needs to be replaced but I have a good general understanding on how this needs to be replaced.

Thanks