Methods of joining components to form vehicle assemblies, such as engine assemblies, are provided. The methods include arranging a first component having a first channel defined therein in a mold, arranging a second component having a second channel defined therein in the mold, and aligning the first and second channel to define a pin-receiving channel. At least one polymeric composite pin is inserted into the pin-receiving channel thereby joining the first and second components, wherein an adhesive is disposed adjacent to at least a portion of the polymeric composite pin.