You've reported an unusually severe problem, but it may be easily fixable.

"Leveling" isn't you're problem. Anything close to level is fine.

You've got several things at least working against you.

Start by verifying that the shipping bolts have been removed so that the machine's suspension is free to work.

Next, you must adjust the bottom feet so that they're each weighted equally or nearly-equally. Equal-weighting of the feet is important because the suspension components bear on them in order to do their job. Get them as close as you can with the machine off. Then put a full load in and be ready with your adjustment tool when the machine spins up to full speed. While its spinning tweak one of the front legs up or down slightly and you'll achieve what you need to.

Once you're certain these things are as they should be it's up to the floor. A suspended floor in a 100-year-old house may be a tough nut. Suspended floors sometimes don't provide a firm enough base....but sometimes they do. It will either work or it won't. However, until you've verified the first two items there's no way to tell.

My stacked machines are on tile over concrete (I live in an 80's highrise). I had them installed on these so for all I know these don't make a bit of difference but the low-end apartment sized Samsung machine I have had a reputation for being a walker and I don't have any problems.

{{!gwi}}

Here is a link that might be useful: gvi

I think Asolo is probably right. I had the same thing with a "possessed" new frigidaire washer.....I found out the plumber had forgotten to remove a couple of the shipping bolts. Once I found them and removed them....my washer was "exorcised".

Asolo...you were right! Silly me, to think that the installers would know what they were doing. Once I found the shipping bolts and got them off, the demon was gone. The stacked machines still vibrate and shake a bit (well within what seems like normal bounds), but they don't move, the house doesn't shake and it doesn't sound like a shuttle is taking off! Thank you!

Running a frontloader (or toploader also, I suppose) without the shipping anchors removed can cause damage to the machine. You might should contact the selling store to make note of it in case any related troubles come up in the near future ... or even tell them you want a service inspection done.

A friend bought a Neptune way back in 2001, installers from the store didn't remove the bolts. The machine was literally leaping up off the floor and slamming itself down. He made them bring a new one.

Glad it worked. However, I must credit the first mention of the idea to respondent "stingo" who first wrote it in the appliances forum before you re-posted here.