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  3. GM 385994

ORIGINAL GM 385994 Saginaw Synchro 66-84 3RD/4TH Or 2ND/3RD

385994 Original Gm Two 66-84 Saginaw 3rd/4th Or 3 Spd 2nd/3rd Synchro Assembly Excellent Used

( Brand: Original Gm ), ( Manufacturer Part Number: 385994 ), ( Items Included: Slider Hub Keys Synchro Rings ), ( Material: Steel ), ( Vintage Part: Yes ), ( Type: Saginaw Synchro Assembly ), ( Manufacturer Warranty: No Warranty ), ( Oe/oem Part Number: Awt302-80 ), ( Surface Finish: Used Cleaned ), ( Universal Fitment: No ), ( Country Of Origin: United States )

Review ORIGINAL GM Two 66-84 Saginaw 3rd/4th Or Spd 2nd/3rd Synchro Assembly Excellent Used

The GM 385994 66-84 Saginaw 3rd/4th speed 2nd/3rd synchro is an essential component of automatic transmission systems found in various General Motors vehicles from the 1966 to 1984 model years. This synchro assembly is specifically designed for the 3rd and 4th gear speeds, with the added function of synchronizing the engagement of the 2nd and 3rd gears.

The synchro, short for synchronizer, is a mechanical device that facilitates smooth and efficient gear changes in an automatic transmission. It works by reducing the force required to mesh gears during a shift, minimizing any unwanted noise or vibration. The GM 385994 is meticulously machined from high-quality materials to ensure precise fitment and optimal performance.

This specific synchro assembly is engineered with a conical friction lining system. The lining system allows the gears to come into contact gradually, as the driver shifts gears, ensuring a seamless transition between speeds. The conical shape of the linings enables the gears to engage in a controlled manner, reducing the wear and tear on the transmission components and providing a more enjoyable driving experience.

The GM 385994 66-84 Saginaw 3rd/4th speed 2nd/3rd synchro is built to last, with robust construction and robust materials that can withstand the rigors of daily driving. However, like any mechanical component, it may eventually wear out and require replacement. If you notice any signs of transmission issues, such as difficulty shifting gears, grinding noises, or a delay in gear engagement, it may be time to consider replacing your synchros, including the GM 385994 assembly.

When it comes time to install the new synchro, it is important to follow the correct procedures to ensure proper installation and function. Consult your vehicle's service manual or a professional mechanic for guidance on the installation process. Proper installation will help maximize the lifespan of the new synchro and ensure optimal transmission performance.

In summary, the GM 385994 66-84 Saginaw 3rd/4th speed 2nd/3rd synchro is a crucial component of the automatic transmission system in select General Motors vehicles. Its conical friction lining system facilitates smooth and efficient gear changes, reducing wear and tear on transmission components and providing a more enjoyable driving experience. When it comes time for replacement, follow the correct procedures for installation to ensure optimal performance and longevity.

Pros and Cons of Buying GM Part Number 385994 for a Saginaw 3rd/4th Speed 2nd/3rd Synchronizer

Introduction:

The GM part number 385994 is a synchronizer used in the Saginaw 3rd/4th speed transmission system. This component ensures smooth gear shifts between the third and fourth gears. In this analysis, we will explore the potential advantages and disadvantages of purchasing this part for your vehicle.

Pros:

1. Improved Driving Experience: A worn-out synchronizer can lead to rough gear shifts and unnecessarily hard shifts between gears. Replacing this part with a new one can significantly enhance the driving experience, making gear transitions smoother and more enjoyable.

2. Long-Term Durability: A new synchronizer is designed to last longer than a worn-out one, which can save you money in the long run. By investing in a new component, you can avoid the need for frequent replacements and potential repairs.

3. Enhanced Transmission Performance: A new synchronizer can improve the overall performance of your transmission system. It can help to reduce slippage, improve torque capacity, and enhance the overall efficiency of your vehicle's powertrain.

Cons:

1. Cost: The cost of purchasing a new synchronizer can be a significant investment, especially for older vehicles. However, considering the long-term benefits and improved driving experience, the cost may be worthwhile for some vehicle owners.

2. Labor Costs: Installing a new synchronizer requires specialized knowledge and tools, which can add to the overall cost of the repair. In some cases, it may be more cost-effective to have the work done by a professional mechanic.

3. Potential For Compatibility Issues: It's essential to ensure that the part you purchase is compatible with your specific vehicle make, model, and year. Using the wrong part can lead to further complications and additional repair costs.

Conclusion:

In conclusion, the decision to purchase GM part number 385994 for a Saginaw 3rd/4th speed 2nd/3rd synchronizer involves weighing the potential advantages against the drawbacks. While the cost may be a significant investment, the improved driving experience, long-term durability, and enhanced transmission performance can make it a worthwhile investment for some vehicle owners. However, it's crucial to ensure compatibility and consider labor costs before making a purchase.

Recommendation:

If you experience rough gear shifts, hard shifts, or notice any other transmission issues that may be related to a worn-out synchronizer, it may be worth considering the purchase of a new one. However, it's essential to do your research, ensure compatibility, and consider all costs before making a final decision. Consulting with a professional mechanic can also help you make an informed decision based on your specific vehicle's needs.

Details:

TWO Saginaw first/second synchro assembly as used in 4 speeds or 2nd/ 3rd 3 speeds,Excellent condition ,no chipped teeth, nice sharp engagement also speed 1st/ reverse shipping included Final sale no what your buying .48 states NO EXPORTS.

part #: 385994 price

  • $174.99

specifications manutransmission:

  • brand: Original Gm
  • mpn: 385994
  • items included: Slider Hub Keys Synchro Rings
  • material: Steel
  • vintage part: Yes
  • type: Saginaw Synchro Assembly
  • manufacturer warranty: No Warranty
  • oe/oem part number: Awt302-80
  • surface finish: Used Cleaned
  • universal fitment: No
  • country of origin: United States

returns manutransmission:

  • policy: No Returns

seller manutransmission:

  • # reviews: 2020
  • city: Huntington Station, New York
  • rating: 100.0%

offer manutransmission:

  • sold: 0
  • options: Ship-to-home
  • quantity: 1
  • started: November 28, 2025
  • availability: In Stock

general manutransmission:

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

shipping manutransmission:

  • carrier: UPS
  • class: Standard
  • type: Fixed
  • transit: 4-8 Days
  • cost: $0.00
  • service: UPS Ground

payments manutransmission:

  • wallet: Paypal
  • credit card: Discover
  • other
items included: slider hub keys synchro rings, vintage part: yes, type: saginaw synchro assembly, manufacturer warranty: no warranty, oe/oem part number: awt302-80, surface finish: used cleaned, universal fitment: no, country of origin: united states,
category: auto parts > car truck parts accessories > transmission drivetrain > manual transmission parts, material: steel, sku: 9520121661599641,

Original Gm 385994 Is Similar To:

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1 offer $174.99 USD
  • Offer #1: $174.99 price + $9.82 shipping estimate = $184.81* total. What you see is what you get New NOS GM 3859984 Saginaw 4 speed 1st 2nd Rev Synchro Assembly 1966-67 Chevy Passenger Cars Including Corvair.+$9.82 shipping

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