diff --git a/examples/SharedMemory/PhysicsClientC_API.cpp b/examples/SharedMemory/PhysicsClientC_API.cpp
index 73c2b5c33..2b2d4451c 100644
--- a/examples/SharedMemory/PhysicsClientC_API.cpp
+++ b/examples/SharedMemory/PhysicsClientC_API.cpp
@@ -2652,7 +2652,7 @@ B3_SHARED_API int b3ChangeDynamicsInfoSetMass(b3SharedMemoryCommandHandle comman
 {
 	struct SharedMemoryCommand* command = (struct SharedMemoryCommand*)commandHandle;
 	b3Assert(command->m_type == CMD_CHANGE_DYNAMICS_INFO);
-	b3Assert(mass > 0);
+	b3Assert(mass >= 0);
 	command->m_changeDynamicsInfoArgs.m_bodyUniqueId = bodyUniqueId;
 	command->m_changeDynamicsInfoArgs.m_linkIndex = linkIndex;
 	command->m_changeDynamicsInfoArgs.m_mass = mass;
diff --git a/examples/SharedMemory/PhysicsServerCommandProcessor.cpp b/examples/SharedMemory/PhysicsServerCommandProcessor.cpp
index e88276d5b..c29d6265c 100644
--- a/examples/SharedMemory/PhysicsServerCommandProcessor.cpp
+++ b/examples/SharedMemory/PhysicsServerCommandProcessor.cpp
@@ -7461,6 +7461,39 @@ bool PhysicsServerCommandProcessor::processChangeDynamicsInfoCommand(const struc
 					mb->getBaseCollider()->getCollisionShape()->calculateLocalInertia(mass, localInertia);
 					mb->setBaseInertia(localInertia);
 				}
+
+				//handle switch from static/fixedBase to dynamic and vise-versa
+				if (mass > 0)
+				{
+					bool isDynamic = true;
+					if (mb->hasFixedBase())
+					{
+						int collisionFilterGroup = isDynamic ? int(btBroadphaseProxy::DefaultFilter) : int(btBroadphaseProxy::StaticFilter);
+						int collisionFilterMask = isDynamic ? int(btBroadphaseProxy::AllFilter) : int(btBroadphaseProxy::AllFilter ^ btBroadphaseProxy::StaticFilter);
+
+						m_data->m_dynamicsWorld->removeCollisionObject(mb->getBaseCollider());
+						int oldFlags = mb->getBaseCollider()->getCollisionFlags();
+						mb->getBaseCollider()->setCollisionFlags(oldFlags & ~btCollisionObject::CF_STATIC_OBJECT);
+						mb->setFixedBase(false);
+						m_data->m_dynamicsWorld->addCollisionObject(mb->getBaseCollider(), collisionFilterGroup, collisionFilterMask);
+
+					}
+				}
+				else
+				{
+					if (!mb->hasFixedBase())
+					{
+						bool isDynamic = false;
+						int collisionFilterGroup = isDynamic ? int(btBroadphaseProxy::DefaultFilter) : int(btBroadphaseProxy::StaticFilter);
+						int collisionFilterMask = isDynamic ? int(btBroadphaseProxy::AllFilter) : int(btBroadphaseProxy::AllFilter ^ btBroadphaseProxy::StaticFilter);
+						int oldFlags = mb->getBaseCollider()->getCollisionFlags();
+						mb->getBaseCollider()->setCollisionFlags(oldFlags | btCollisionObject::CF_STATIC_OBJECT);
+						m_data->m_dynamicsWorld->removeCollisionObject(mb->getBaseCollider());
+						mb->setFixedBase(true);
+						m_data->m_dynamicsWorld->addCollisionObject(mb->getBaseCollider(), collisionFilterGroup, collisionFilterMask);
+					}
+				}
+				
 			}
 			if (clientCmd.m_updateFlags & CHANGE_DYNAMICS_INFO_SET_LOCAL_INERTIA_DIAGONAL)
 			{
diff --git a/examples/pybullet/examples/changeDynamicsMass.py b/examples/pybullet/examples/changeDynamicsMass.py
new file mode 100644
index 000000000..fcd625638
--- /dev/null
+++ b/examples/pybullet/examples/changeDynamicsMass.py
@@ -0,0 +1,15 @@
+import pybullet as p
+import time
+
+p.connect(p.GUI)
+cube2 = p.loadURDF("cube.urdf",[0,0,3], useFixedBase=True)
+cube = p.loadURDF("cube.urdf", useFixedBase=True)
+p.setGravity(0,0,-10)
+timeStep = 1./240.
+p.setTimeStep(timeStep)
+p.changeDynamics(cube2,-1,mass=1)
+#now cube2 will have a floating base and move
+
+while (p.isConnected()):
+	p.stepSimulation()
+	time.sleep(timeStep)
\ No newline at end of file
diff --git a/src/BulletDynamics/Featherstone/btMultiBody.h b/src/BulletDynamics/Featherstone/btMultiBody.h
index be4c5d638..00f91e6ce 100644
--- a/src/BulletDynamics/Featherstone/btMultiBody.h
+++ b/src/BulletDynamics/Featherstone/btMultiBody.h
@@ -469,6 +469,11 @@ public:
 		return m_fixedBase;
 	}
 
+	void setFixedBase(bool fixedBase)
+	{
+		m_fixedBase = fixedBase;
+	}
+
 	int getCompanionId() const
 	{
 		return m_companionId;