GM 39503006 Muncie Trans Cover Plate Serviceable 4-SPEED M-21 MT12.31.25

( Brand: Gm ), ( Manufacturer Part Number: 39503006 ), ( Type: M21 Side Cover Plate Assy ), ( Material: Aluminum ), ( Vintage Part: Yes ), ( Country Of Origin: United States )

Review GM Muncie 4-speed Trans Side Cover Plate Assy M-21 Alum Serviceable

Introducing the GM Muncie 39503006 4-speed transmission cover plate, specifically designed for the M-21 aluminum serviceable Munciedrive train with an mounting dimension of 12.31 inches by 25 inches. This cover plate is a crucial component of your transmission system, protecting the internal components from external elements and enhancing the overall aesthetics of your vehicle.

Manufactured by GM, this cover plate is engineered to meet the highest standards of quality and durability. Crafted from robust aluminum material, it offers superior resistance to corrosion, ensuring a long service life even in harsh environments. The plate features a sleek, streamlined design that not only complements the look of your M-21 transmission but also facilitates efficient cooling by allowing air to circulate around the vital components.

The GM Muncie 39503006 4-speed transmission cover plate is a direct replacement for the original equipment, ensuring a perfect fit and seamless integration with your existing transmission system. The mounting holes are pre-drilled and aligned to match the factory specifications, eliminating the need for additional modifications or custom fabrication.

Installing this cover plate is a straightforward process, thanks to its serviceable design. The plate is easily removable, allowing you to access the transmission components for maintenance, repairs, or upgrades. By providing unobstructed access to the transmission internals, this cover plate makes routine maintenance a breeze and helps you save time and money in the long run.

In summary, the GM Muncie 39503006 4-speed transmission cover plate is an essential upgrade for your M-21 aluminum serviceable Muncie transmission. With its robust aluminum construction, sleek design, and easy-to-install feature, this cover plate not only bolsters the performance and durability of your transmission system but also adds a touch of style to your vehicle.

Pros and Cons of Buying a GM Muncie M21 Alum Serviceable Trans Cover Plate (MT12.31.25)

The GM Muncie M21 Alum Serviceable Trans Cover Plate (MT12.31.25) is a popular aftermarket part for those who own or are working on a classic GM vehicle with the M21 4-speed transmission. In this article, we will discuss the advantages and disadvantages of purchasing this specific transmission cover plate.

1. Lightweight: The aluminum material used in the manufacture of this transmission cover plate is lighter than the standard steel cover. This reduces the overall weight of the transmission and can lead to improved fuel economy and easier handling.

2. Durability: Aluminum is a more durable material than steel, which makes the cover plate more resistant to corrosion and damage. This can save you money in the long run by reducing the need for frequent replacements.

3. Aesthetic Appeal: The aluminum cover plate gives the transmission a more modern and visually appealing look. This can be an important consideration for those who are restoring a classic car and want to make it stand out.

1. Cost: The aluminum cover plate is typically more expensive than the standard steel cover. This can be a significant investment for some people, especially if they are working on a budget.

2. Installation: Installing the aluminum cover plate may require some additional modifications to the transmission, such as drilling new holes for the bolts or using special gaskets. This can add to the overall cost and complexity of the project.

3. Maintenance: Although aluminum is more durable than steel, it is still susceptible to damage if not properly maintained. This can include protecting the cover plate from exposure to harsh chemicals or extreme temperatures.

The GM Muncie M21 Alum Serviceable Trans Cover Plate (MT12.31.25) offers several advantages over the standard steel cover, including improved weight, durability, and aesthetic appeal. However, it also comes with some disadvantages, such as a higher cost, more complex installation process, and increased maintenance requirements. Ultimately, whether or not to purchase this transmission cover plate depends on your specific needs and budget. If you value the benefits of lighter weight and durability, and are willing to invest in the additional cost and time, then this may be the right choice for you. If, on the other hand, you are working on a tight budget or prefer a more straightforward installation process, then the standard steel cover may be a better option.

If you are working on a classic GM vehicle with the M21 4-speed transmission and are looking for a high-quality, durable transmission cover plate, then the GM Muncie M21 Alum Serviceable Trans Cover Plate (MT12.31.25) is an excellent choice. However, be sure to carefully consider the additional cost, installation requirements, and maintenance needs before making your purchase. If you are on a tight budget or prefer a more straightforward installation process, then the standard steel cover may be a more practical option for you.

Details:

Muncie M21 trans aluminum side cover plate assy,ORIG we got a 4-speed that was left to the elements. Periodically our info is wrong. Items have come up missing or unavailable, sometimes due to double listing errors. However,our team does occasionally make mistakes.

Secondhand Tools. We even miss the boat once in a while. Rough has rust pitting.

part #: 39503006 prices

• $79.99-$99.00

specifications manutransmission:

• brand: Gm
• mpn: 39503006
• type: M21 Side Cover Plate Assy
• material: Aluminum
• vintage part: Yes
• country of origin: United States

shipping manutransmission:

• class: Expedited
• cost: $9.98
• service: USPS Priority Mail
• transit: 5-10 Days
• carrier: USPS
• type: Fixed

payments manutransmission:

• credit card: Diners-club
• wallet: Google-pay
• other

seller manutransmission:

• rating: 100.0%
• city: Cocoa, Florida
• # reviews: 9670

returns manutransmission:

• paid by: Buyer
• time: 30 Days
• policy: Returns Accepted

general manutransmission:

• condition: Used
• Car Truck Parts Accessories > Transmission Drivetrain > Manual Transmission Parts

offer manutransmission:

• sold: 0
• availability: In Stock
• options: Ship-to-home
• quantity: 1
• started: December 31, 2025

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