We often get questions from people about whether or not they can/should replace their original 3-button keyfob with a 4-button remote that has the same FCC ID or that looks equivalent. Several factors come into play in answering this question.
Generally speaking, if you are buying a replacement car or truck remote for factory keyless entry system, you should buy the same part you already have. The safest way to get the right part is to call your dealership, give them your VIN, and ask them for the current OE part number for the remote that came with your car. Then use that number to shop for a replacement part.
Definitely do not use visual characteristics as your basis for buying a replacement remote. Just because remotes may look the same does not mean they operate the same. Chrysler, GM, Nissan, Honda and Toyota all make remotes that are visually identical but not interchangeable.
Also, if you think you are going to gain a remote function by replacing a 3-button remote with a 4-button remote, you will be disappointed. For instance, if your truck came with a 3-button remote, you will not be able to turn it into a remote start vehicle simply by buying the related 4-button remote with a remote start button.
Many people think that all they have to do is match the FCC ID number to get the correct replacement part. While this is true in many cases it is not true in all cases. Here are a couple of links for remotes where you CAN replace the 3-button remote with a 4-button remote and not lose any functionality: