Hi everyone,
I’m working on a truck simulation in Unreal Engine, and I’ve encountered an issue: when one of the truck’s wheels is off the ground (not in contact with the surface), it continues to spin indefinitely.
Hey @Hengamestudios — sounds like a fun project! 
The issue you’re seeing with the wheel spinning while off the ground is actually pretty common in physics-based vehicle setups in Unreal Engine.
What’s Likely Happening:
When the wheel loses contact with the ground, Unreal’s default PhysX / Chaos wheel setup often keeps applying torque unless explicitly told not to. This usually means:
- The wheel isn’t updating contact info fast enough
- OR the simulation isn’t cancelling residual torque
What to Try:
1. Suspension / Wheel Contact Check
Use GetWheelState to check if the wheel is in air — then reduce motor torque accordingly.
You can implement a small “in-air torque fade” to gradually reduce spin when airborne.
2. Use Sub-Stepping (if using Chaos)
Inaccurate updates can cause physics to act erratically at high speeds or low frame rates. Enable sub-stepping in project physics settings for smoother force handling.
3. Check Blueprint Logic
If you’re manually applying force or torque based on input, make sure it’s gated by a “wheel on ground” condition.
Bonus Tip for Debugging Complex Assets:
When you’re working on vehicle simulations — especially as they grow — it’s easy to lose track of what’s tested, fixed, or broken across wheel types, terrain conditions, and physics tweaks.
That’s why we built Asset Optics — a plugin that lets you:
Add comments or checklists directly to your truck asset or physics Blueprint- Track bugs like “rear left wheel spinning bug” or “verify spring damping”
Sync it all to a web dashboard for clarity when debugging across scenes or builds
We’ve found it really helpful on vehicle-heavy projects where multiple systems interact (suspension, collisions, materials).
Let us know if that helps! And if you find a creative fix, definitely share it — could help a lot of other devs working on off-road sims and driving physics. 
