Hey folks long time listener first time caller. I've got a 2013 e550 coupe and from what I can see,feel my front driver side wheel looks as if it's running out when I hit 60mph. No real shake in the steering wheel but throughout the front end of the car. I can't really see anything that is noticeabley damaged. I thought it was maybe the drive shaft support bearing and or the flex discs so I replaced them with no change that's when I stuck my head out the window at 60mph and noticed the wheel looking like it was running out of round when I hit 60. No strange tire wear or visible tire damage. This all started when I made a drive over the mountain pass and encountered alot of water/slush on the roadway but nothing that would have made me think that i damaged anything. Car has about 130k miles on it.

 

Hey, and welcome I'm trying to picture you sticking your head out and looking, because I wouldn't be able to unless I had cruise control on, unbuckled and half crawled out the window. I'm picturing it now, thanks for the visual :p
So what did you see now? "running out"? do you mean acting like it's out of balance, or actual runout?
If out of balance I guess I'd check the weights, which do sometimes fall off. If so, odds are the vibe would be minimal as you seem to have described. I spoze I would swap it with another wheel, or do a full rotation to see if it moves.
Another option I've done is put the car on jacks/blocks or whatever and take it up to the problem speed.
I'd also put bushings on my suspect list, especially if they're original, which could cause all kinds of various wheel movement/flopping around. One way I check those, after a visual, is look at the suspension parts while someone else turns the wheel back n forth. With the weight of the car on the tires it takes a lot of force and you will see what parts have slack.

When the motor mounts on my 2013 E350 (RWD) died I too suspected the center bearing on the driveshaft, but I think it was simply transmitting driveline vibes through the mount to the frame, and probably creating driveline vibes since the angle was now off. That wouldn't make the wheel do whatever you saw, but fyi on the vibes. Another fyi is I use a phone app that measures vibe freq. I simply hold the phone against the center console, dash, door or whatever hard surface, then math out what's at that freq. No guarantees, per the aforementioned 350 that saw driveshaft vibes, but the vibe was real and at that freq.

As for the water; I got nothing. Can't imagine it would do anything in any way, but who knows. I can tell you a couple water related stories that probably won't apply to you, but info is info, and you may find it entertaining:
When I bought my truck it had violent vibes ~90 or 100, I forget exactly. And I mean violent!! Like borderline losing control and crashing violent. So I let off the gas (obviously) and it instantly and completely goes away. I stop and poke around, but everything looks fine. I get back on the freeway and it's fine, and of course inch up that speed to see what happens. The moment I hit that same exact speed it's instantly doing it again! No transition phase, it's either smooth or completely violent. Wth right? It was the left rear and I can see it in the rear view looking as if it was a ball bouncing around the wheel well so fast it was just a blur. I made a mental note; keep it under that speed...
Not long after I bought some used tires from some hole in the wall used tire place and when they broke the bead on that tire about a gallon of nasty white water came out. Aside from the tire guy being rather displeased, it explained everything in a second. The white stuff was liquid tire sealant. I can only assume the previous owner kept adding it until a gallon later it finally stopped leaking? So fyi if you used tire sealant recently. While I've never used modern goo type tire sealer, I suppose it could settle while parked, and not smooth out enough while driving to make it slightly (compared to mine) out of balance? Another, that many an offroader can tell you, is mud can get on the inside of the wheel and of course throw it out of balance. I assume you checked for that, but missing wheel weights are far more likely in comparo. Whenever I see the tape residue of weights, I wonder, was that the previous set of weights, or current set? Worst case you simply have re-balanced, even if just to rule it out.

Meanwhile, more details on what exactly you saw the wheel doing, please.

 

Ok let me start by saying that it wasn't the easiest thing to do going 60+ and getting myself far enough outside the car window to get a decent look at the wheel but desperate times! And it is more than just a slight vibration. It's heavy enough that I could see it clearly when looking at the wheel while doin 60 mph. Its heavy enough that I originally thought that I had blown a couple radial belts and expected a baseball sized bubble in the tire when I first had to pull over when it happened. I did notice that the control arm inner bushing wasnt in the best shape so I ordered a set today. I'm hoping this takes care of the issue cause the cars been a non driver for almost a month and thank God the weather's been good where I'm at so I've been able to take my Road King to and from work I'll check back in when I install the control arms on Monday.

 

If not the re-balancing or the control arm bushings, then have the wheel checked to ensure it is not bent and runs true. Check the mounting flange on the rotor to ensure that it is true and clean as well. Finally front wheel bearings are notorious for causing wobble. See other threads on here for that issue and the associated repairs.