300SE1993

I've seen a few videos about this but cannot seem to get a clear answer on what exactly the problem is. Of course I am hoping I just need a new bearing, but for those of you familiar with this situation, please share your feedback

chassis

Can you post photos specifically showing your concern?

300SE1993

In the video, about 1/2 way through, you can see the bearing bouncing around when I move the axle. It's right where the intermediate shaft goes into the oil pan. That's what I am trying to figure, is it a bad bearing? Missing retaining clip? Bad oil pan?

habbyguy

I'd suggest pulling the axle, then removing the retainer C-clip, and see what's there. It should be obvious whether the problem you're seeing is the inner portion of the bearing moving, or the outer race.

If it's the first, pull and replace the bearing. If it's the second... it's gonna be a bit more complicated. ;-)

300SE1993

OK, this is really helpful. When I look at everything closely and compare it to a new bearing, it looks like my bearing is completely intact. It seems like the bearing may have separated from the outer race. I am assuming the outer race is part of the oil pan itself, which would make for an extremely expensive repair. I have heard that you can use loctite 660 to repair this, but I don't think that's really a good route as I want to keep this car a long time.

So I guess that leads to another question. Is the outer race a part of the oil pan? Can it be replaced separately?

habbyguy

If the bearing IS intact, the inner and outer races aren't moving relative to each other. The outer race is NOT part of the oil pan, but would be pressed into the pan.

So if you can see the outer race (for reference, a large, metal cylinder that the ball bearings roll around inside) moving around inside the hole in the pan, you're going to have to do one of several things...
1) Replace the pan (probably the most likely to be a 100.000% reliable fix)
2) Cobble something together to "rejuvenate" the bearing seat. I'm really not sure what the options are (kind of depends on how bad the movement is, though it looks "plenty bad" in the video). There may be a "repair sleeve" that can be pressed or "glued" into place. I've never seen one though.
3) Perhaps a machine shop would be able to ream the oil pan seat to a new, larger, round (!) dimension that would allow the use of a machined "adapter" (OD matches the new hole, ID the bearing outer race), or maybe a different bearing (with the "new OD and original ID").
4) Sell the car and pretend it never happened ;-)

300SE1993

Oh, my, this is what I was afraid of. Thanks for clarifying. Yep, it definitely is looking like I need a new oil pan because I can definitely see the outer race moving around inside the hole in the pan. I really like the car and think the rest of it will last so I will probably just bite the bullet and have this done.

habbyguy

I'm hoping that the pan replacement is easier on a GLK250 than a GLK350. I did a quick online cost lookup, and the numbers were surprisingly low. I know that means less than nothing. ;-)

300SE1993

I have a call in to the dealer to get a quote on pan replacement.

habbyguy

Ouch. Hope you can find an indy mech who is familiar with the breed... Have to guess that a dealer is going to be pretty spendy.

And FWIW, I did read a thread or two about fixing the problem with "Loctite", but suspect that's more of an option when the amount of play is minimal (yours doesn't seem to fall into that category). Still, it might be worth at least reading up on some of the options, depending on how isolated that bearing seat is from anything that could be damaged by machining or stray Loctite or similar compound.

300SE1993

I had a (probably very bad) idea that if I could wedge something in there to hold the bearing in place that it might actually work. I am thinking the bearing itself is fine.

habbyguy

There are compounds that are supposed to be used to fill in a gap like that one. I'm guessing (SWAG warning) that the stresses on that bearing aren't TOO bad.

I'd personally suggest swapping the bearing. Mainly because you really need to pull it out anyway to properly clean the pan recess, and "just in case" (they're not spendy from what I saw).

Spending a total of about 2 minutes . Seems to have good reviews being used in similar situations - I'd suggest reading through all the reviews and see what you think...

300SE1993

I had thought about using a compound similar to that, but then if the bearing does actually fail, the intermediate shaft would be harder or impossible to get out.

chassis

No.

chassis

No.

chassis

The bearing failed, normal at high mileage and age. It sounds like it might have taken the oil pan with it.

The linkshaft (shaft going through the oil pan) may have been bouncing around for long enough that the splines which engage with the front axle differential may be compromised.

Minimum repair, based on the information provided: new oil pan and new bearing

Possible repair, only known once it is apart: new oil pan, new bearing, new linkshaft (probably only comes as an entire axle shaft), and new front axle differential.

The only way to know is to open it up and see.

300SE1993

OK, before you all flame me for what I'm about to post, I am well aware this is a horrible idea, but think of it as experimental. There's always the off chance it works LOL

habbyguy

I think the five minute estimate might be optimistic. ;-)

I think the two-part "epoxy" has at least a fighting chance of working. It is supposed to harden to a pretty solid state, which just might hold the bearing in place (under normal circumstances, there should be very little stress on that bearing). There's no down side that I can see. If you replace the bearing when you insert the goop, you're probably never going to have to touch it again. If it doesn't work, then you're going to be swapping the pan anyway.

The only other non-pan-swap-save I can think of would be to use a cylinder reamer (like you'd use to clean up the cylinder walls in a small engine) to return the pan recess to a consistent, round size. Then figure out some sort of shim (slice of a thin wall tube) can be pressed in, or perhaps find a bearing that fits the new hole AND the intermediate shaft (I'd start by looking at McMaster - Carr or WW Grainger).

300SE1993

The 5 minute estimate was about right LOL. I definitely need to do something eventually. The weird thing is I hear no noises from it, feel no vibrations and honestly would not have even known it was a thing without having shook the axle. I wonder how many of us are blissfully unaware we're driving like this.

habbyguy

I think it all comes down to how little stress there is on that bearing under normal conditions. That's the only reason I think that there's some chance that the epoxy solution might actually work. I would add the proviso that I'd hesitate to start out on a cross-country trip until I had some serious miles on the epoxy without any issues.

300SE1993

Thanks for your help! Now I am trying to figure out how in the world that happened in the first place. Only thing I can come up with is that the outer race was somehow spinning against the oil pan and wallowing out the hole.

habbyguy

I doubt the bearing was spinning until the hole in the pan was well and truly munged. I'd suspect there was a past imbalance (maybe a bad CV axle?) that caused enough force to create a bit of a gap, and from there it just devolved into what you're seeing now.

chassis

Folks, the bearing failed. It reached the end of its life. This is normal, expected, and not surprising.

The owner(s) ignored the failed bearing.

The now-useless bearing failed to do its job, which is to hold the linkshaft in place. The result is a mucked-up oil pan. And possibly a mucked-up axle differential spline - this is unknowable until the parts are disassembled.

There is no mystery about this.

300SE1993

You can say that, but that's not true. First off, the car was very likely with that problem already when I bought it at 144K miles. Second, there are absolutely no symptoms. It drives perfectly smooth without vibration or noise. I stumbled onto the problem accidentally while under the car checking things.

I am guessing a large number of people with 4Matics have this same issue and have no clue it's an issue because of no symptoms.

300SE1993

For those few of you who are interested in my saga, I have 2 updates:

1. Several thousand miles since I posted this, the issue has not gotten any worse so I continue driving it.
2. I was able to successfully get the zip tie solution to work by using a longer sip tie and wrapping it around the oil line by the pan. It has significantly reduced the amount of movement and has been staying in place.