Game/GigLine/Source/GigLine/GigLineVehicle.cpp

@@ -313,6 +313,25 @@ void AGigLineVehicle::Tick(float DeltaSeconds)
 		}
 	}
 
+	// If the Chaos vehicle never came into existence (no wheels), its movement component has no
+	// valid state to drive, and continuing to tick it writes whatever is in that empty state back
+	// onto the actor - which is the only explanation that fits a still body and a moving actor.
+	if (!bMoverStopped && SettleElapsed > 2.5f)
+	{
+		bMoverStopped = true;
+		if (const UChaosWheeledVehicleMovementComponent* WheelComp =
+				Cast<UChaosWheeledVehicleMovementComponent>(GetVehicleMovementComponent()))
+		{
+			UE_LOG(LogTemp, Warning,
+				TEXT("GigLine vehicle: stopping the mover - wheels=%d at Z %.0f"),
+				WheelComp->Wheels.Num(), GetActorLocation().Z);
+		}
+		if (UMovementComponent* Mover = GetVehicleMovementComponent())
+		{
+			Mover->SetComponentTickEnabled(false);
+		}
+	}
+
 	// One-shot diagnostic: why zero wheels. Wheels are built in CreateVehicle(), which runs only
 	// when the physics state produced a vehicle, so the useful facts are whether the mesh is
 	// simulating and whether it carries a physics asset at all.
@@ -349,6 +368,36 @@ void AGigLineVehicle::Tick(float DeltaSeconds)
 					Vel.X, Vel.Y, Vel.Z, Angular.X, Angular.Y, Angular.Z, Body->GetMass(),
 					Body->IsSimulatingPhysics() ? 1 : 0, Body->IsAnySimulatingPhysics() ? 1 : 0);
 			}
+			if (Body && Body->GetSkeletalMeshAsset())
+			{
+				// Do the wheel setups name bones the mesh actually has? If not, CreateVehicle()
+				// bails before it ever builds a wheel.
+				TArray<FName> Bones;
+				Body->GetBoneNames(Bones);
+				FString BoneList;
+				for (int32 i = 0; i < Bones.Num() && i < 20; ++i)
+				{
+					BoneList += Bones[i].ToString() + TEXT(" ");
+				}
+				FString SetupList;
+				if (const UChaosWheeledVehicleMovementComponent* WheelComp =
+						Cast<UChaosWheeledVehicleMovementComponent>(GetVehicleMovementComponent()))
+				{
+					for (const FChaosWheelSetup& S : WheelComp->WheelSetups)
+					{
+						SetupList += S.BoneName.ToString() + TEXT(" ");
+					}
+				}
+				UE_LOG(LogTemp, Warning, TEXT("GigLine vehicle bones: %d [%s] | setups [%s]"),
+					Bones.Num(), *BoneList, *SetupList);
+			if (const UMovementComponent* Mover = GetVehicleMovementComponent())
+			{
+				UE_LOG(LogTemp, Warning,
+					TEXT("GigLine vehicle mover: updated=%s ticking=%d"),
+					Mover->UpdatedComponent ? *Mover->UpdatedComponent->GetName() : TEXT("none"),
+					Mover->IsComponentTickEnabled() ? 1 : 0);
+			}
+			}
 			{
 				const USkeletalMesh* Asset = Body ? Body->GetSkeletalMeshAsset() : nullptr;
 				UE_LOG(LogTemp, Warning, TEXT("GigLine vehicle mesh asset: %s"),

Game/GigLine/Source/GigLine/GigLineVehicle.h

@@ -83,5 +83,6 @@ private:
 
 	float SettleElapsed = 0.f;
 	bool bMassSet = false;
+	bool bMoverStopped = false;
 	bool bSettleReported = false;
 };

TODO.md

@@ -32,6 +32,18 @@ GigLine vehicle diag:     mesh=1 simulating=1 physasset=yes setups=4 wheels=0
 - **Gravity** - `global_gravity_z = 0.0` and the character falls normally, so the world pulls down.
 - **Mass** - the 1500 kg override applies (logged), and the body still does not rise.
 
+### Measured after the transform finding
+
+```
+bones:  6 [VehicleRig root Wheel_FL Wheel_FR Wheel_RL Wheel_RR]
+setups: [Wheel_FL Wheel_FR Wheel_RL Wheel_RR]        -> names match, suspect 3 is gone
+mover:  updated=VehicleMesh ticking=1
+stop:   mover tick disabled at 2.5 s (Z 2001); at 3.0 s the actor is still at Z 2258
+terrain: CTF_USE_COMPLEX_AS_SIMPLE, 0 box elements  -> no invisible lid to be ejected from
+```
+
+So the wheel bones match, the terrain has no proxy lid, and stopping the mover did not stop the climb - meaning either the stop does not take effect (something else re-enables or writes the transform every frame) or a second writer exists.
+
 ### Suspects, in order
 
 1. **Component hierarchy**: a pawn whose root is the mesh while the physics state belongs to another component behaves exactly like this - correct box, correct mass, near-zero velocity, moving actor, 1 cm bounds.