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Castrol TranSynd 668 Full-Synthetic Automatic Transmission Fluid, 5 Gallon Pail

$195.99

204 ratingsSource: Amazon

Confirm quantity, package contents, selected variation, current offer details, and store terms before placing the order.

About this item

  • TranSynd is a full-synthetic, automatic transmission fluid designed specifically for ALLISON transmissions / TES 468 is now covered by TranSynd 668
  • Allows for extended drain intervals of up to 300,000 miles / 48 months in general-duty transmissions and up to 150,000 miles / 48 months in severe-duty transmissions
  • 12 times longer drain intervals than conventional and other non-TES 668 and non0-TES 295 fluids
  • Shear stability that helps maintain a stable viscosity which provides wear protection in gears throughout the drain interval
  • Improved gear protection, extended anti-shudder durability and extended clutch-friction durability

Before you order
  • Confirm the part number, position, dimensions, and connector details shown on this page.
  • Compare the listing with the part currently installed on your vehicle.
SKU: D-B0977Q8S49 Category:

Description

TranSynd is a full-synthetic, automatic transmission fluid designed specifically for ALLISON transmissions.

Imported customer feedback

What customers reported

4.7 / 5 204 ratings

Source: Amazon. These reviews were imported from the source marketplace and are not reviews of purchases made on this website.

8 reviews for Castrol TranSynd 668 Full-Synthetic Automatic Transmission Fluid, 5 Gallon Pail

  1. Aspen

    Imported from Amazon. This is not a review of a purchase made on this website.

    External marketplace context: Verified Purchase

    legitdid the double fluid change on my 2019 chevy 2500 since i didn’t know when it was done last or what kind of fluid and it has 126k miles. she shift so SMOOTH now it’s wonderful it makes me so happy that my truck is happy :3also very glad to know that i won’t have to do this again for a very long time with this stuff. 300k fluid change interval is insane lolmy advice tho: get a good pail pump that lists how much fluid per pump so you’re not guessing and having to check the dipstick a buncha times and a long hose so you’re not having to lift a big 5 gallon bucket into your truck’s engine bay lol

  2. Tykhon

    Imported from Amazon. This is not a review of a purchase made on this website.

    External marketplace context: Verified Purchase

    I bought this to do my transmission service on the Allison 1000. Let me tell you I thought I bought way too much initially but ended up using around 2/3 of the pail so this is by far the most efficient method of buying this. The only unfortunate thing is you have to pour it into a separate container to measure it and put it in the truck.

  3. Howard Dinsmore

    Imported from Amazon. This is not a review of a purchase made on this website.

    External marketplace context: Verified Purchase

    Used this in my 2011 Tiffin with Allison 3000 Trans. This is the recommended fluid so I am hoping for trouble free running. Good price for this product.

  4. JOEL C.

    Imported from Amazon. This is not a review of a purchase made on this website.

    External marketplace context: Verified Purchase

    Best oil for Allison HD trans

  5. Customer

    Imported from Amazon. This is not a review of a purchase made on this website.

    External marketplace context: Verified Purchase

    This is sold by evey diesel store online for the alison 1000 transmission. I’m pissed. I’ve used castrol for 30 years. I’d recommend them to anyone… until last week. We talked to castrol over the phone. It was the best for the alison. The newest formula. We called castrol 3 days later to ask if it was okay to use in the transfer case as well… castrol says on the second call ” not only is it not okay to use in the transfer case, but it doesn’t meet the requirements for the alison 1000 transmission either. Now I’m the not so proud owner of a 5 gallon bucket of transmission fluid that isn’t usable and castrol won’t refund exchange or even admit mistake. What crap customer service for a long time favorite company.2004.5 chevy 2500hd lly extended cab 4×4

  6. Miguel

    Imported from Amazon. This is not a review of a purchase made on this website.

    External marketplace context: Verified Purchase

    My rv work good after change the oil transmission

  7. Scott Vincent Allen

    Imported from Amazon. This is not a review of a purchase made on this website.

    External marketplace context: Verified Purchase

    Good value and service.

  8. Dan De Bonis

    Imported from Amazon. This is not a review of a purchase made on this website.

    External marketplace context: Verified Purchase

    Great price and seller. Packaged very well.

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Product facts

Specifications

Canonical product
MP-US-B0977Q8S49
Source product ID
B0977Q8S49
Category
Oils & Fluids / Transmission Fluids
Available images
5

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An identity-first transmission fluids listing organized around stable product references and available compatibility evidence.

Fit and size notes

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Specification notes

  • Canonical product: MP-US-B0977Q8S49
  • Source product ID: B0977Q8S49
  • Category: Oils & Fluids / Transmission Fluids
  • Available images: 5

Before you buy

  • Match the complete identifier, side, position, connector, dimensions, and visible design with the existing part.
  • Treat uncertain vehicle notes as a buying aid, not as a confirmed fitment guarantee.