Bogie pitch trimmers / Truck positioners
Sounds like you're getting into the world of bogie/truck positioning.
'Tilt' of the landing gear, i.e. the rake angle is something different. Most main gears have a slight negative rake for passive stability, while nosegear has a positive rake for active stability.
On gears with 4 or 6 wheel bogies/trucks depending whether you're an Airbus or a Boeing, the angle the bogie 'flies at' is known as the bias angle.
Landing gear bays have very tight clearances, ALL the space is used by design. Depending on the airframe space-claim decisions, and whether the bogie/truck positioner can work in tension, compression, or both, a bias angle is defined to be optimal for stowage of the landing gear by the landing gear design team.
Another consideration is bogie/truck dynamic reactions on landing - a bogie gear may oscillate about centre very rapidly on a hard impact landing, so a toe-down angle or toe-up angle might be preferred depending on your bogie pitch trimmer performance.
Toe down can be better because you get the load spread over all 4/6 tyres sooner on landing, and all brakes can all start working straight away.
Conversely, the A330 toes-up bogie pitch mechanism actually works during rotation, and supposedly helps to achieve a lower minimum unstick speed because it gives a couple of degrees extra angle of attack before the tail touches the deck.
Hope that helps!