Wobbly wheels on my model....

It appears that your dummies/axis for [Wheel_LF] moved, even the slightest offset can break the position, but your Screenshot makes it hard to tell.

You have a few options to try and sort the issue out.

1. Rename [Wheel_LF] to something different to prevent issues and merge in the one from the stock .z3d that came with the base and move the materials to the correct positions in the hierarchy.

2. Dismiss the LODs and reset the dummy axis to the mesh. (Under the display section, use the copy local axis tool and select the mesh, then the dummy helper for the wheel. Reset the children or mesh LODs to the parent to make sure everything is aligned and then redo the LODs). Do note that this runs a slight risk that if the wheel is moved that it would remain out of the original position and might look off compared to normal.

If your wheels all seem fine in zmod then I've seen 2 things cause this
1. To many parts on the car. When you export it will tell you how many items there are, if the number is higher then 235 I think or somewhere around that I can't remember the exact number. (rare unless you're packing in a bunch of misc's + sirens + etc., only way to fix is to condense or remove parts.)

2. At some point while moving something the main axis/dummy for the export name was uncentered from the world causing all the axis to shift strangly causing wheels, doors, and parts to not work correctly. To correct this just select the main first dummy (usually named something like "police" or "fpiu" after the type of car) and reset it to the world.