* Wheel Bolt Pattern: This is the most crucial factor. Both trucks *should* have the same bolt pattern (the number of lug nuts and their spacing), but it's always best to verify. A mismatch here means the wheel won't even mount.
* Wheel Offset: This is the distance between the wheel's mounting surface and its centerline. Different offsets can cause clearance issues with the suspension, brakes, or body. A 2003 wheel might have a slightly different offset than a 1999 wheel, potentially causing rubbing.
* Wheel Diameter and Width: While a larger diameter wheel might fit, it could affect speedometer accuracy and may require a larger tire to maintain the correct overall diameter. A wider wheel may rub against the suspension or body.
* Tire Size: Even if the wheel fits, the tire size needs to be compatible with the truck's specifications to avoid rubbing or other problems.
In short: You need to check the specifications of both the 2003 F-150 wheel and your 1999 F-150. Look for the bolt pattern (e.g., 5x5.5" or 5x139.7mm), wheel offset, wheel diameter, and width. If these specs match closely, the wheel is more likely to fit. If you're unsure, consult a tire professional or a Ford parts specialist.
