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TRIAX Marine Ultra 25W-40 4-Stroke Full Synthetic Marine Engine Oil (5 Gallon Pail)

  • Based on 71 reviews
Condition: New
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$119.99 Why this price?

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Availability: In Stock.
Fulfilled by TRIAX Lubricants LLC

Arrives Jun 7 – Jun 9
Order within 5 hours and 15 minutes
Available payment plans shown during checkout

Size: 5 Gallon Pail


Features

  • Designed for NMMA FC-W 4-Stroke outboard engines; use in gasoline-fueled four-stroke inboards, outboards, inboard/outboards, supercharged watercraft engines and personal watercraft
  • True full synthetic; twice the life of conventional and synthetic blends oil and twice the protection
  • Unmatched corrosion protection, even in continuous salt water use, including up to two years of storage; excellent stability and viscosity control for long term high temp operation
  • Friction modified for exceptional wear protection, less heat, better fuel economy, and significantly reduced wear
  • High film strength and durability under high torque and power output conditions

Manufacturer: ‎TRIAX Lubricants LLC


Brand: ‎Triax


Model: ‎Marine


Item Weight: ‎40.1 pounds


Product Dimensions: ‎12 x 12 x 16 inches


Country of Origin: ‎USA


Item model number: ‎Marine


Manufacturer Part Number: ‎MARINE25W40


Date First Available: April 5, 2022


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Jun 7 – Jun 9

Yes, absolutely! You may return this product for a full refund within 30 days of receiving it.

To initiate a return, please visit our Returns Center.

View our full returns policy here.

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Top Amazon Reviews


  • Never been this impressed with a jug of oil!
Size: 5 Quart Jug
In addition to being made in the USA and a full synthetic 5qt jug at a very competitive price, this product has its own spout for easy pouring!! I've never seen such a unique and useful feature on a jug of oil. The built-in spout made pouring the oil very easy and did not require a separate funnel. I am very impressed and will be purchasing this item again for the next boating season. ... show more
Reviewed in the United States on September 26, 2023 by DaYoops DaYoops

  • Great Price And Pouring Spout Container!
Size: 5 Quart Jug
Great price, made in the USA, and the Container has a 3" pull out pouring spout, was real handy to manage
Reviewed in the United States on September 23, 2023 by Brad

  • Priced to impress
Size: 5 Quart Jug
Seems to be a quality synthetic marine engine oil at a great price. Will know for sure only after hours of run time like any other non Quicksilver brand oil.
Reviewed in the United States on June 19, 2023 by Hikestick

  • Great value
Size: 5 Quart Jug
Love to support smaller companies who supply a quality product at a much better value. Full synthetic oil at the blended price of other companies and a full 5 quarts where they offer 4 quart containers. Do recommend and will buy again.
Reviewed in the United States on May 9, 2023 by Drewbstew

  • Good value
Size: 5 Quart Jug
Fast shipping, 5qt containers, full synthetic. I was surprised container was not wrapped in plastic, especially since the cap was loose. Foil seal was intact, no harm but I believe these liquids are required to be made spill proof.
Reviewed in the United States on February 11, 2023 by Amazon Customer

  • Good value
Size: 5 Quart Jug
I put this oil in a 60 hp Mercury outboard. I use other Triax oils in my compressor and ATV with good results. Also made in the USA.
Reviewed in the United States on March 20, 2023 by Rickjrfshrmn

  • Good alternative to Mercruiser oil
Size: 5 Quart Jug
I have a Mercruiser engine in my boat that specifies, (as expected), Mercruiser brand 25W-40 weight oil. This oil is a semi synthetic oil sold by the gallon and costs about 30% more than a 5 quart container of Mobil 1 or other premium full synthetic oils. I've been looking at switching to one of the full synthetic's but there are people online that contend that marine oil has a different wear and corrosive additive package added than oil normally used in cars. I'm skeptical that this is the case and think Mercruiser is just over charging for their name but didn't want to take the chance. I happened to stumble on the TRIAX marine oil and decided to give it a shot. I don't know anything about TRIAX but the ratings information on the container are identical to those on the Mercury oil only it is full synthetic and 5 quarts costs less than 4 provided by Mercury. Without having the oil analyzed by some independent testing lab I decided to take them at their word and assume that since it was designed for marine applications and since it meets all the same ratings that it should perform as well or better than the name brand. I've been running it in my boat now for a few weeks without any issues (didn't expect there would be) as lubrication problems tend to take sometime time to manifest themselves. That said, I doubt I'm going to see any adverse effects and suspect that this oil, being a full synthetic, will actually perform better than the more expensive Mercury oil. ... show more
Reviewed in the United States on August 30, 2022 by Rich

  • Alternative To Name Brand 25W-40, And Better Quality
Size: 5 Quart Jug
I needed an alternative this year as the name brand oil was not available. I came across this oil and I'm glad I did. This oil is cheaper and better quality. It meets and exceeds the oil requirements for my engine and it is full synthetic, not synthetic blend. The container is also a 5 quart jug as opposed to a 4 quart like competitors, so it is half to 1/3 the price of name brand. I will be using this product moving forward in my engines. ... show more
Reviewed in the United States on December 12, 2022 by Advele

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