MM1327100 MAZDA Manual Trans Locking Rear Differential Miata

Review MAZDA Mazdamm 1327100 Manual Trans Locking Rear Differential 3.91 Ratio for MIATA 1999–2005

The Mazda MM1327100 is a locking rear differential assembly specifically designed for Mazda Miata models manufactured between 1999 and 2005. This component is engineered to replace the standard open differential, providing enhanced traction and improved handling capabilities.

The locking feature of this differential ensures that both rear wheels rotate at the same speed during high torque situations. This is particularly beneficial when driving on low-traction surfaces such as snow, ice, or gravel. By minimizing the difference in wheel speed, the Mazda MM1327100 significantly reduces wheel slip and maximizes the available grip.

This differential assembly comes with a gear ratio of 3.91:1. A lower gear ratio provides more torque and better acceleration. When combined with the locking differential, this gear ratio results in improved traction and power delivery to the rear wheels.

The Mazda MM1327100 is a direct replacement for the original equipment on these Miata models, ensuring a seamless installation process. It is also engineered to meet or exceed OEM specifications, ensuring reliable and consistent performance.

This differential assembly is designed with a durable cast iron housing, providing excellent heat dissipation and resistance to wear. The gears are precision-machined from high-strength steel, ensuring smooth and efficient power transfer.

In summary, the Mazda MM1327100 locking rear differential assembly is an excellent upgrade for Mazda Miata owners seeking improved traction, enhanced handling, and increased power delivery. This component is engineered to meet or exceed OEM specifications, ensuring reliable and consistent performance, and is a direct replacement for Miata models manufactured between 1999 and 2005.

The Mazda MM1327100 is a locking rear differential for the 1999-2005 Miata with manual transmission, featuring a gear ratio of 3.91. This component can be beneficial for enhancing traction and improving handling in various driving conditions, especially during low-traction situations such as off-roading, snow, or rain. Here are some potential pros and cons of installing this differential:

1. Enhanced Traction: The locking differential ensures that both rear wheels receive the same amount of power during a turn. This leads to improved traction and stability, allowing the driver to maintain control in slippery conditions.

2. Improved Handling: With the power evenly distributed to both rear wheels, the Miata's handling will be more responsive and predictable, allowing for faster cornering speeds and better overall performance.

3. Off-Road Capability: The locking differential can help the Miata perform better off-road by providing better traction and reducing wheel slip, making it more capable in challenging terrain.

4. Customization: Installing a locking differential is an excellent way to customize your Miata and make it stand out from the crowd. It can also add value to the car if you plan on selling it in the future.

1. Cost: The cost of purchasing and installing a locking differential can be substantial, especially when considering the labor costs for installation.

2. Weight: The locking differential adds weight to the rear of the Miata, which can negatively impact fuel efficiency and handling performance.

3. Complexity: Installing a locking differential is a complex process that requires specialized tools and knowledge. It is recommended to have a professional perform the installation to ensure it is done correctly.

4. Maintenance: The locking differential may require more frequent maintenance than a standard differential due to its additional complexity.

The Mazda MM1327100 locking rear differential for the 1999-2005 Miata manual transmission can provide numerous benefits, such as enhanced traction, improved handling, and off-road capability. However, it also comes with drawbacks, such as the high cost, added weight, complexity, and increased maintenance requirements. Ultimately, the decision to install a locking differential depends on your driving preferences, budget, and the desired level of customization for your Miata. If you frequently encounter low-traction conditions, off-road terrain, or simply want to enhance your Miata's performance, then the pros may outweigh the cons for you. However, if budget and maintenance concerns are a priority, you may want to consider other options.

Details:

All used items will show normal signs of use such as nicks, scuffs, and scratches. I will definitely come back to his page when i'm looking for something in the future. 100% will purchase from again. And I m glad they respectfully accepted my offer which made the value of product worth buying.

The also did an excellent job packaging a very oddly shaped part roll bar. These folks at j auto are top notch and deserve a full review. Part number mm 13271 body type convertible, engine, condition, odometer 244641, exterior color strati blue, paint code 25e, interior gray, trim c8. Component was exactly as described and in the photos on listing.

Quality assurance. Not only where they flexible on their price, communication, /pics were perfect. Shipping time was excellent. The packaging was by far the best i've ever seen for a heavy part.

Parts are extremely well priced as with super fast shipping. Every order is meticulously packaged with extra protection and padding. The value was excellent. This item is used but in good working condition.

I was very satisfied with it. Will definitely do business again. If I could leave a better that 5 star review would. All parts are tested and inspected for reliability performance.

I'm looking forward to doing business with them again. Fast reliable. Items are exactly as you see them in the photo, no BS. 10/10 experience.

They take pride in their work. An overall great buying experience and an excellent value. The engine wiring harness was just as pictured there only one damaged wire connector I had to re splice, disappointing but not a big deal. Contact for fitment purchase price.

I'm happy with the value compared to new. Packaging would have been sufficient to ship a Faberge egg. It also arrived right around the time it said would.

specifications differentialsdepo:

• for models: Miata
• for years: 1999–2005
• brand: Mazda
• mpn: Mm1327100
• part type: Manual Tran
• placement on vehicle: Rear
• performance part: No
• tag: 585673
• item warranty: 30 Days

returns differentialsdepo:

• paid by: buyer
• policy: returns accepted
• time: 60 days

offer differentialsdepo:

• started: march 11, 2026
• in stock #: 2
• sold #: 10
• availability: in stock
• prices: $1149.79–$3145.60
• item condition:
  • Used
  • New
• options: ship-to-home
• best offers: true

shipping differentialsdepo:

• class: economy
• transit: 2-6 days
• service: economy
• type: fixed

seller differentialsdepo:

• city: marshallville, ohio
• rating: 100.0%
• # reviews: 37974

general differentialsdepo:

• category: Auto Parts > Transmission Drivetrain > Differentials > Assemblies

payments differentialsdepo:

• other
• credit card: visa
• wallet: paypal