* Wheel Bolt Pattern: The 2008 Silverado uses a specific bolt pattern (the number of lug nuts and their spacing). The 16" wheels *must* match this pattern. If they don't, they won't fit. Check your existing wheels or the vehicle's specifications to know this pattern.
* Wheel Offset and Backspacing: The offset and backspacing determine how far the wheel sits in or out relative to the hub. Incorrect values can cause rubbing against the suspension, brakes, or body. You need to find wheels with an offset and backspacing compatible with your truck. This is critical and often overlooked. Consult a wheel fitment guide or a tire shop that specializes in truck tires and wheels.
* Brake Caliper Clearance: 16" wheels might not have enough space for your brakes, especially if you have larger brakes than standard. You *must* confirm clearance before purchasing.
* Tire Size: While you can fit smaller diameter wheels, the tire size is just as important. Using a significantly smaller diameter tire will affect your speedometer accuracy, odometer readings, and potentially your transmission's performance. You need to ensure the overall diameter of the new tire and wheel combination remains relatively close to the original 20" setup. A tire shop can help calculate the correct tire size.
* Suspension: While unlikely, exceptionally wide 16" wheels could cause rubbing issues against the suspension components.
In short: It's *possible*, but it requires careful research to ensure proper fitment. Don't just buy any 16" wheels and tires. You need to verify the bolt pattern, offset, backspacing, brake caliper clearance, and overall tire diameter. A reputable tire shop is your best resource for this information and to ensure a safe and proper fit. They can check compatibility and help you choose the right size and type of winter tire for your truck.
