Here's how to find out:
1. Check your vehicle's documentation: Your owner's manual or registration papers might specify the axle type and details, though this information isn't always explicit.
2. Look at the axle itself: This is the most direct method. Jack up the vehicle safely and securely using jack stands. Locate the axle you need the rotor for (front or rear). Visually inspect the rotor. Note its diameter and thickness. Take pictures and measurements to compare with parts available online or at an auto parts store.
3. Use a parts lookup website or app: Websites like AutoZone, Advance Auto Parts, Napa Auto Parts, and RockAuto allow you to enter your vehicle's Year, Make, Model, and Engine to find the correct parts. They'll often show diagrams and specifications to confirm you're choosing the right rotor. This is generally the easiest and most reliable method.
4. Visit an auto parts store: A knowledgeable parts counter person at an auto parts store can help you identify the correct rotor based on your vehicle's year, make, and model. They can also look up the part number for you based on your vehicle's VIN (Vehicle Identification Number). Provide them with the VIN for the most accurate information.
Important Considerations:
* Front vs. Rear: Front and rear axles almost always use different rotors.
* ABS (Anti-lock Braking System): If your Jimmy has ABS, the rotors will likely have a different design than those without ABS. Make sure to specify this when ordering parts.
* 4WD vs. 2WD: Four-wheel-drive models may have different rotors than two-wheel-drive models, especially in the front.
* Year and Model Variations: Rotors can change even within the same model year of the GMC Jimmy. Precise year and model details are crucial for accurate identification.
Don't rely solely on visual inspection, as similar-looking rotors can have different specifications. Always use a reputable parts lookup resource or consult a parts professional to ensure you purchase the correct rotors. Improperly sized rotors can affect braking performance and safety.