What size speakers fit a 1978 F-150?

In a 1978 Ford F-150, the front door speakers typically fit 6x8 inch sizes, while the rear speakers can vary depending on the configuration, often accommodating 6x9 inch or 5.25 inch speakers. It's important to check the specific trim and options of your truck, as aftermarket modifications may also affect speaker sizes. When upgrading, consider using adapters if needed for a proper fit.