Landscape spline complex collision ignores collision material

Hello. I am creating a driving game where so far I have a landscape with a spline for the road. The spline uses a simple road mesh which is basically a rectangle. I have set the default landscape collision physical material to a physical material I created with low friction (i.e. grass). For the road mesh I use another material (“asphalt”) which has much more friction. My goal is to have high friction road surface, surrounded by lower friction grass.

The problem I am facing is that if I leave the simple and complex collision on the road mesh, when the vehicle is driving over the road that has an incline, I see that the wheels aren’t really touching the mesh by quite a bit. I solved this by setting “Collision Complexity” to “User Complex Collision As Simple”. Then the wheels are touching the mesh perfectly at any incline and all angles. However, after I do that, the collision physical material of the mesh is ignored and the default landscape collision physical material is used instead. I tried removing the complex collision, I tried changing the collision box, but nothing.

So, I either have one collision physical material for the entire landscape regardless if the vehicle is on the landscape or the spline mesh… or if I use simple collision for the mesh, then wheels don’t align properly on slopes. I am rather new to UE, so maybe I’m doing something incorrectly or there is something I don’t know about such a case. Any advice or help would be very appreciated. BTW. I am using “Wheeled Vehicle” class for the vehicle.

I have the same problem. Hoping to find some answer…