FEA delivers unrealistic displacement values

[Anonymous]

I performed a FEA simulation on a structure (attached assembly file named "Assembly FEA" inside the folder) which shows that the maximum displacement on the bushings of the structure (round rubber parts near the bottom of the assembly) is 4.2 mm, when the maximum displacement that it should obtain is about 2.4 mm, which I calculated separately and checked multiple times. 
The whole structure is made out of steel, except for the rubber rings and bushings which provide a flexible support to the structure. So I created a specific rubber matterial (named 60055) for those 2 parts, and entered the corresponding material properties of it (according to our rings and bushings supplier).

During the simulation process, three warnings appear: 
- Model Separates into two independent components
- Soft Spring was added
- The deformation is large compared to the model size. Please verify that load and constraint settings are properly scaled.

And I verified everithing plenty of times, the loads, materials and constraints are all correct. Do you have any clue of what could I be missing or doing wrong? 

Note.: I should mention that I also tested the bushing and rings displacements in another simplified assembly, to see if the material behaved and deformed the way it should, and it did, so I know for a fact that the bushing and ring dimensions and properties are correct.