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AMSOIL SAE 50 Long Life 100% Synthetic Transmission Oil

Product code : FTF1G-EA

4.4 star rating
Read 7 reviews

AMSOIL SAE 50 Long Life 100% Synthetic Transmission Oil

Product code : FTF1G-EA

4.4 star rating
Read 7 reviews
Current price:

$69.19

Retail Price
Warning - Click here for Proposition 65 information for this product
Estimated delivery by Mon, Jun 8 to Columbus - 43215.

  • Specifically Engineered for 500,000-Mile Service in Over-The-Road Trucks

    • Maximizes gear and bearing life
    • Helps operators save money
    • Promotes smooth shifts
    • Helps extend seal life and prevent leaks

  • We offer easy returns for customers. If your product is unused and unopened, you may return it within 30 days for a full refund of the purchase price. View full AMSOIL Return Policy.

  • We accept Visa, Mastercard, American Express, Discover and PayPal, and provide secure checkout and encrypted payment processing.

About this item

  • AMSOIL SAE 50 Long-Life Synthetic Transmission Oil is specially formulated to meet the demanding requirements of manual transmissions found in high-torque, heavy-duty line-haul trucks and other commercial applications. Its synthetic base oils and premium additives help reduce wear (see photos), improve shifting and extend transmission life throughout drain intervals of up to 500,000 miles/five years. Compared to conventional fluids, Long-Life Synthetic Transmission Oil can help operators reduce maintenance costs and increase productivity.

    Resists Wear
    AMSOIL Long-Life Synthetic Transmission oil's synthetic base oils withstand the pressures of high-load, high-torque applications. As a result, it resists viscosity loss due to mechanical shear to provide a durable lubricating fluid film for increased wear resistance and longer transmission life.

    To prove its effectiveness, AMSOIL installed SAE 50 Long-Life Synthetic Transmission Oil in line-haul trucks and placed them into real-world service. After more than 500,000 miles, a transmission was disassembled and inspected by a calibrated ASTM rater. Results reveal Long-Life Synthetic Transmission Oil provided outstanding wear protection in all critical components (see images).

    Year-Round Performance
    AMSOIL Long-Life Synthetic Transmission oil's high viscosity index translates into better high- and low-temperature performance compared to conventional fluids. In cold weather, it provides easier shifts and reduced fluid drag for increased fuel economy. Its exceptional thermal stability inhibits chemical breakdown and sludge formation at high operating temperatures to help transmissions run cleaner.

    Inhibits Foam
    Churning gears introduce air into the fluid, causing foam. When bubbles between gear surfaces collapse, metal-to-metal contact and increased wear result. Long-Life Synthetic Transmission Oil contains foam inhibitors to ensure formation of a strong lubricating film and excellent wear protection.

    FTF Wear Photos





    Seal Friendly
    Long-Life Synthetic Transmission Oil is compatible with seals to help prevent leaks and extend seal life.

    Applications
    AMSOIL SAE 50 Long-Life Synthetic Transmission Oil is excellent for use in manual transmissions requiring an SAE 50 lubricant found in heavy-duty equipment. It is recommended for applications specifying any of the following:

    • Eaton* PS-164 Rev. 7
    • API GL-1 and MT-1
    • Navistar*/International* TMS 6816
    • Mack* TO-A Plus
    • ZF* Freedomline
    • Meritor* 0-81
    • Rockwell*/Eaton/Fuller* CD-50 (PS-081)

    Service Life
    Follow the OEM drain interval for synthetic oil up to 500,000 miles or five years, whichever comes first.

    AMSOIL PRODUCT WARRANTY
    AMSOIL products are backed by a Limited Liability Warranty. For complete information visit www.amsoil.com/warranty/.

    HEALTH AND SAFETY
    This product is not expected to cause health concerns when used for the intended applications and according to the recommendations in the Safety Data Sheet (SDS). An SDS is available online at www.amsoil.com or upon request at (715) 392-7101. Keep Out of Reach of Children. Recycle used oil and bottle.

    *All trademarked names and images are the property of their respective owners and may be registered marks in some countries. No affiliation or endorsement claim, express or implied, is made by their use. All products advertised here are AMSOIL-engineered for use in the applications shown.

  • Data Bulletin

    Warranty

    SDS



  • 4.4 star rating
    Based on 7 reviews
    See all customer reviews
    • 5 star rating
      Quality Oil
      By  ROSS,  a  Verified Buyer  on  June 01, 2026
      Love this oil for my trucks, great value with a membership.
      Bottom Line
      Yes, I would recommend this to a friend.
      Was this review helpful?
    • 5 star rating
      transmissiob
      By  THOMAS,  a  Verified Buyer  from  SC  on  October 23, 2025
      Outstanding transmission oil sample results land lower operating temps
      Bottom Line
      Yes, I would recommend this to a friend.
      Was this review helpful?
    • 5 star rating
      Quality
      By  ANDREW,  a  Verified Buyer  from  Missouri   on  October 20, 2025
      I switched my M35A2 transmission over to this much better shifts better lubrication. Better heat transfer, less wear and less transmission.Oil changes highly recommend this product
      Bottom Line
      Yes, I would recommend this to a friend.
      Was this review helpful?
    • 5 star rating
      A++++ Best trans oil I’ve used by far !!
      By  JAMES,  a  Verified Buyer  from  Upstate New York  on  January 16, 2023
      By far best manual trans fluid I’ve used !!
      Bottom Line
      Yes, I would recommend this to a friend.
      Was this review helpful?
    • 1 star rating
      Just an average conventional product
      By  Mike,  a  Verified Buyer  from  NJ  on  April 03, 2018
      I was hoping to get a nice transmission oil. But after changing to this one. Shifting became more rough. Feels like it turns thinner when it picks up temperature. But I do like very much signature series diesel oil and differential fluid is great. And I wish amsoil had some kind of high end of transmission fluid.
      Bottom Line
      No, I would not recommend this to a friend.
      Was this review helpful?
    • 5 star rating
      Great quality
      By  Wade,  a  Verified Buyer  from  North Carolina  on  October 15, 2017
      This gets used in my 76 cj5 transmission swap does great
      Bottom Line
      Yes, I would recommend this to a friend.
      Was this review helpful?
    • 5 star rating
      Yes
      By  Andriy,  a  Verified Buyer  from  Edmonton  on  May 10, 2017
      Transmission
      Bottom Line
      Yes, I would recommend this to a friend.
      Was this review helpful?

  • Specifically Engineered for 500,000-Mile Service in Over-The-Road Trucks

    • Maximizes gear and bearing life
    • Helps operators save money
    • Promotes smooth shifts
    • Helps extend seal life and prevent leaks

  • We offer easy returns for customers. If your product is unused and unopened, you may return it within 30 days for a full refund of the purchase price. View full AMSOIL Return Policy.

  • We accept Visa, Mastercard, American Express, Discover and PayPal, and provide secure checkout and encrypted payment processing.

  • AMSOIL SAE 50 Long-Life Synthetic Transmission Oil is specially formulated to meet the demanding requirements of manual transmissions found in high-torque, heavy-duty line-haul trucks and other commercial applications. Its synthetic base oils and premium additives help reduce wear (see photos), improve shifting and extend transmission life throughout drain intervals of up to 500,000 miles/five years. Compared to conventional fluids, Long-Life Synthetic Transmission Oil can help operators reduce maintenance costs and increase productivity.

    Resists Wear
    AMSOIL Long-Life Synthetic Transmission oil's synthetic base oils withstand the pressures of high-load, high-torque applications. As a result, it resists viscosity loss due to mechanical shear to provide a durable lubricating fluid film for increased wear resistance and longer transmission life.

    To prove its effectiveness, AMSOIL installed SAE 50 Long-Life Synthetic Transmission Oil in line-haul trucks and placed them into real-world service. After more than 500,000 miles, a transmission was disassembled and inspected by a calibrated ASTM rater. Results reveal Long-Life Synthetic Transmission Oil provided outstanding wear protection in all critical components (see images).

    Year-Round Performance
    AMSOIL Long-Life Synthetic Transmission oil's high viscosity index translates into better high- and low-temperature performance compared to conventional fluids. In cold weather, it provides easier shifts and reduced fluid drag for increased fuel economy. Its exceptional thermal stability inhibits chemical breakdown and sludge formation at high operating temperatures to help transmissions run cleaner.

    Inhibits Foam
    Churning gears introduce air into the fluid, causing foam. When bubbles between gear surfaces collapse, metal-to-metal contact and increased wear result. Long-Life Synthetic Transmission Oil contains foam inhibitors to ensure formation of a strong lubricating film and excellent wear protection.

    FTF Wear Photos





    Seal Friendly
    Long-Life Synthetic Transmission Oil is compatible with seals to help prevent leaks and extend seal life.

    Applications
    AMSOIL SAE 50 Long-Life Synthetic Transmission Oil is excellent for use in manual transmissions requiring an SAE 50 lubricant found in heavy-duty equipment. It is recommended for applications specifying any of the following:

    • Eaton* PS-164 Rev. 7
    • API GL-1 and MT-1
    • Navistar*/International* TMS 6816
    • Mack* TO-A Plus
    • ZF* Freedomline
    • Meritor* 0-81
    • Rockwell*/Eaton/Fuller* CD-50 (PS-081)

    Service Life
    Follow the OEM drain interval for synthetic oil up to 500,000 miles or five years, whichever comes first.

    AMSOIL PRODUCT WARRANTY
    AMSOIL products are backed by a Limited Liability Warranty. For complete information visit www.amsoil.com/warranty/.

    HEALTH AND SAFETY
    This product is not expected to cause health concerns when used for the intended applications and according to the recommendations in the Safety Data Sheet (SDS). An SDS is available online at www.amsoil.com or upon request at (715) 392-7101. Keep Out of Reach of Children. Recycle used oil and bottle.

    *All trademarked names and images are the property of their respective owners and may be registered marks in some countries. No affiliation or endorsement claim, express or implied, is made by their use. All products advertised here are AMSOIL-engineered for use in the applications shown.

  • Data Bulletin

    Warranty

    SDS



  • 4.4 star rating
    Based on 7 reviews
    See all customer reviews
    • 5 star rating
      Quality Oil
      By  ROSS,  a  Verified Buyer  on  June 01, 2026
      Love this oil for my trucks, great value with a membership.
      Bottom Line
      Yes, I would recommend this to a friend.
      Was this review helpful?
    • 5 star rating
      transmissiob
      By  THOMAS,  a  Verified Buyer  from  SC  on  October 23, 2025
      Outstanding transmission oil sample results land lower operating temps
      Bottom Line
      Yes, I would recommend this to a friend.
      Was this review helpful?
    • 5 star rating
      Quality
      By  ANDREW,  a  Verified Buyer  from  Missouri   on  October 20, 2025
      I switched my M35A2 transmission over to this much better shifts better lubrication. Better heat transfer, less wear and less transmission.Oil changes highly recommend this product
      Bottom Line
      Yes, I would recommend this to a friend.
      Was this review helpful?
    • 5 star rating
      A++++ Best trans oil I’ve used by far !!
      By  JAMES,  a  Verified Buyer  from  Upstate New York  on  January 16, 2023
      By far best manual trans fluid I’ve used !!
      Bottom Line
      Yes, I would recommend this to a friend.
      Was this review helpful?
    • 1 star rating
      Just an average conventional product
      By  Mike,  a  Verified Buyer  from  NJ  on  April 03, 2018
      I was hoping to get a nice transmission oil. But after changing to this one. Shifting became more rough. Feels like it turns thinner when it picks up temperature. But I do like very much signature series diesel oil and differential fluid is great. And I wish amsoil had some kind of high end of transmission fluid.
      Bottom Line
      No, I would not recommend this to a friend.
      Was this review helpful?
    • 5 star rating
      Great quality
      By  Wade,  a  Verified Buyer  from  North Carolina  on  October 15, 2017
      This gets used in my 76 cj5 transmission swap does great
      Bottom Line
      Yes, I would recommend this to a friend.
      Was this review helpful?
    • 5 star rating
      Yes
      By  Andriy,  a  Verified Buyer  from  Edmonton  on  May 10, 2017
      Transmission
      Bottom Line
      Yes, I would recommend this to a friend.
      Was this review helpful?

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