Basically you need to have intermediate objects attached to the madCar plugin, because trying to just bake the motion of an object set as a madCar wheel won’t work, because Max doesn’t see the wheel as moving, it’s the madCar object moving. Anyway here’s what you do:
Setup your madCar and attach the actual geometry of your car just like normal, setting geometry wheels to have the madCar controller, etc.
Animate madCar.
Create a dummy object for each of the pieces of the car, and point constrain and orientation constrain each dummy to it’s geometry object. (So take dummy for front left tire, add a point constraint on the dummy so it’s attached to the the front left tire geometry, then do the same with an orientation constraint.) The point constrain will get the movement and the orientation constrain will get the rotation.
Once the constraints are setup, you can select the dummy and go to the motion tab of the command panel, press the trajectories button, and setup your collapse options. All that really is, is what frame to start at, what frame to end at, and how many samples (or keyframes) you want in between. So if you start at 0 end at 100, 100 samples will get you a key every frame, 50 samples will get you a key every two frames, 25 samples will get you a key every 4 frames, etc.) So once the settings are setup, you just press “collapse” to collapse the transformations of the dummy objects. This will turn the point and orientation constraint controllers into normal Pos X/Y/Z and Rot X/Y/Z controllers, so now the dummies have the animation baked in and are in no way connected to anything madCar, you could delete the madCar and the geometry objects and the dummies would still have their animation. (provided you did it right, may want to confirm at this point)
At this point you just change the controller on the geometry objects back to a normal controller, and then link the geometry object to the dummy. The geometry object doesn’t have any keys, but will inherit all the movement from the dummy. You’ll probably need to align the geometry to the dummy so the pivots/orientation line up to begin with, but other than that you should be able to repeat this for all 5 objects (4 wheels & chassis) and when you’re done you’ll have baked animation with no connection to the madCar object.
Hope that makes sense, if not keep asking questions. 