Wheelbarrow replacement parts are not universally interchangeable. Wheelbarrows come in various designs, sizes, and materials, which means that parts such as wheels, handles, trays, and frames can differ significantly between models and manufacturers. 
Wheels, for instance, vary in diameter, width, and axle size. Some wheelbarrows have pneumatic tires, while others have solid rubber or foam-filled tires. The axle length and diameter can also differ, affecting compatibility. Handles can be made from wood, metal, or plastic, and their length and attachment method can vary. Trays are made from materials like steel, plastic, or poly, and their size and shape are specific to the wheelbarrow's design.
Manufacturers often design their wheelbarrows with proprietary parts to ensure optimal performance and durability, which can limit interchangeability. While some generic parts are available, they may not fit all models or provide the same level of performance.
When replacing parts, it's essential to check the specifications of the original components and compare them with the replacements. Consulting the manufacturer's guidelines or contacting customer support can help ensure compatibility. In some cases, it may be necessary to purchase parts directly from the manufacturer or authorized dealers to guarantee a proper fit.
In summary, while some wheelbarrow parts may be interchangeable between similar models, there is no universal standard for replacement parts. It's crucial to verify compatibility with the specific wheelbarrow model to ensure proper function and safety.