How do I know if I have 8.8 or 9.75 rear end?
When it comes to maintaining or upgrading your vehicle, knowing the specifications of your rear axle is crucial. The 8.8 and 9.75 rear ends are common in many vehicles, particularly in trucks and SUVs. This guide will help you identify which rear end your vehicle has, so you can make informed decisions about repairs, upgrades, or replacements.
Why It’s Important to Know Your Rear End Type
The rear end, or differential, plays a vital role in transferring power from the engine to the wheels. The size and type of your rear end can affect your vehicle's towing capacity, performance, and compatibility with aftermarket parts. Knowing whether you have an 8.8 or 9.75 rear end ensures you purchase the correct parts and avoid costly mistakes.
Steps to Identify Your Rear End
Follow these steps to determine whether your vehicle has an 8.8 or 9.75 rear end:
- Check the Axle Tag: Most vehicles have a metal tag attached to the differential cover. This tag contains important information, including the axle size. Look for numbers like "8.8" or "9.75" stamped on the tag.
- Measure the Differential Cover: If the tag is missing or unreadable, you can measure the differential cover. The 8.8 rear end typically has a more oval-shaped cover, while the 9.75 has a larger, more rounded cover. Use a tape measure to confirm the dimensions.
- Count the Bolts: The number of bolts on the differential cover can also help identify the rear end. The 8.8 rear end usually has 10 bolts, while the 9.75 may have a different configuration. Refer to your vehicle's manual for specifics.
- Consult Your Vehicle’s Manual: Your owner’s manual or a repair guide specific to your vehicle model will often list the rear end type. This is a reliable source of information if you’re unsure.
- Use the VIN Decoder: Some manufacturers encode axle information in the Vehicle Identification Number (VIN). Use an online VIN decoder or consult your dealership to extract this information.
Common Vehicles with 8.8 and 9.75 Rear Ends
To give you a general idea, here are some vehicles commonly equipped with these rear ends:
- 8.8 Rear End: Found in many Ford vehicles, including the Ford Mustang, F-150 (older models), and Explorer.
- 9.75 Rear End: Typically found in heavier-duty trucks like the Ford F-150 (newer models) and F-250.
When to Seek Professional Help
If you’re still unsure about your rear end type or need assistance with repairs, it’s always a good idea to consult a professional. At Kevin’s Autos, we specialize in diagnosing and repairing all types of rear ends. Our experienced technicians can help you identify your axle type and provide expert advice on maintenance or upgrades.
Contact us today to schedule an appointment or discuss your vehicle’s needs. With years of experience and a commitment to quality service, Kevin’s Autos is here to keep your vehicle running smoothly!
Frequently Asked Questions
How do I know what size rear differential I have?
Without an ID tag, differentials are identified by the number of cover bolts, the distinctive shape of the cover, the number of ring gear bolts, and ring gear diameter. They can also be identified by whether the center section is an integral or dropout design.
How to tell the difference between 8.8 and 9.75 rear end?
On the passenger's side upper and lower corners, there's two semi-circular divots that can easily be seen when looking at the cover from straight on. While the Super 8.8's cover has a bulge for the ring gear, it's not anywhere near as pronounced as the 9.75's.
How can I tell what gear ratio I have without pulling cover?
I have my buddy holding the other Tire. I start spinning this and I'm watching the other. One. That's one full rotation right there.
What Ford has a 8.8 rear end?
8.8 Solid Axle
Ford first used the 8.8 axle in 1983 model year trucks and is still in production for the Ford Ranger and Ford F-Series. It was also used in the Ford SUVs until Independent suspension replaced the solid axle.
What Ford trucks have the 8.8 rear end?
Ford first used the 8.8 axle in 1983 model year trucks and is still in production for the Ford Ranger and Ford F-Series. It was also used in the Ford SUVs until Independent suspension replaced the solid axle.
How do you tell what size differential you have?
Ring gear diameter can be a helpful way to identify which differential you have. The ring gear diameter is measured across the face of the gear. To obtain the ring gear diameter, simply place a tape measurer across the gear. This can be tricky if the ring gear & carrier are still in the housing.
How can you tell what type of rear end you have?
If the ID tag or stamp is missing or unreadable, differentials can be identified by the number of cover bolts, the distinctive shape of the cover, the number of ring gear bolts, and ring gear diameter. They can also be identified by whether the center section is an integral or dropout design.
What vehicles have a Ford 9.75 rear end?
Popular Applications:
| Ford F-150 | 1997 to Current | Rear |
|---|---|---|
| Ford F-150 Raptor | 2010 to Current | Rear |
| Ford Transit | 2015 to Current | Rear |
| Ford E Series Vans | 1999 - 2014 | Rear |
| Ford Expedition | 1997 - 2014 | Rear |
How do I know my rear end ratio?
If you are not sure about your results when using the wheel rotation method, the number of teeth is stamped on the ring gear. The small number is the pinion-gear tooth count. The large number is the ring-gear tooth count. To find the gear ratio, divide the big number by the little number.
How do I identify my Ford 8.8 rear end?
Almost all 8.8s—and all post-1986 Ford rearends—have letters and numbers. The first number refers to the plant where it was built, and the next three refer to the ratio and type.
