Animation Deformation From Blender To Unreal

First off, I would like to state that I and another have been searching the web for quite some time now trying to find a fix for this issue. We have done just about everything to our knowledge.

As mentioned above when exporting from Blender into UE4 using .fbx, the animation comes out partially distorted. At first the imported model is fine, but as soon as the animation is applied that’s where the issue lies. Below is a picture of the distorted animation.

There are no modifiers in the blend file (other than the armature modifier). All bones have an applied loc, rot, and scale when in the main pose. The screen shots below show the export process from Blender v2.75.

I unchecked Add Leaf Bones because it was causing an issue adding a root bone on export. When we import it into UE4, we drag and drop it into the Content Browser. We leave all the default settings, but make sure it imports the animations as well.

This is what the animation does after importing to UE4. As you can see, the feet and lower legs are the only bones having issues everything else is as needed. This happens with every animation from this project.

Not sure how to upload the Blend file, every time I try it states it failed to load. Happens on all .blend files I try.

Any help would be much appreciated. Thank you.

Usually I export twice from Blender. At first only the skeleton mesh without anims and a second time the animation. Afterwards I import the skeletal mesh first and choose that skeleton when I import the animation. However it could even be something else in your case… hard to tell with this screenshot. Did you get any error at import like some weights was missing and put to root bone? If yes then normalizing your weights in Blender meight help. UE4 and Blender differ in that case. Animations in Blender could look good even if the sum of your weight is lets say just 0.7 on some vertices. It seems Blender ignores that or normalizes that weights to 1 if you play the animation while UE4 puts that missing weight to the root bone which could look pretty strange afterwards.