LODs are for performance boost for GPU/CPU. Yes you can - mostly of the metin .gr2 models have LOD files which are stored inside model or as separated .gr2 files with lod_01/2/3 at the end of the parent model name.
For example: c1-009-hotel.gr2 and c1-009-hotel_lod_01.gr2
Or disable loading LODs in client source for granny .cpp/h files
Post edit: \GameLib\ActorInstanceData.cpp
void CActorInstance::SetShape(DWORD eShape, float fSpecular)