---
product_id: 41663211
title: "Fleet Supreme 15W-40 API CK-4 Full Synthetic Heavy Duty Diesel Engine Oil | Moly Boron Friction Modified | Extended Drain (5 Gallon)"
brand: "triax"
price: "74217 kr"
currency: ISK
in_stock: true
reviews_count: 8
category: "Triax"
url: https://www.desertcart.is/products/41663211-fleet-supreme-15w-40-api-ck-4-full-synthetic-heavy
store_origin: IS
region: Iceland
---

# 4-6% MPG Improvement 15W-40 Full Synthetic Viscosity Cold Start Protection to -45°F Fleet Supreme 15W-40 API CK-4 Full Synthetic Heavy Duty Diesel Engine Oil | Moly Boron Friction Modified | Extended Drain (5 Gallon)

**Brand:** triax
**Price:** 74217 kr
**Availability:** ✅ In Stock

## Summary

> 🚛 Drive Supreme, Save More: The Ultimate Diesel Oil Upgrade

## Quick Answers

- **What is this?** Fleet Supreme 15W-40 API CK-4 Full Synthetic Heavy Duty Diesel Engine Oil | Moly Boron Friction Modified | Extended Drain (5 Gallon) by triax
- **How much does it cost?** 74217 kr with free shipping
- **Is it available?** Yes, in stock and ready to ship
- **Where can I buy it?** [www.desertcart.is](https://www.desertcart.is/products/41663211-fleet-supreme-15w-40-api-ck-4-full-synthetic-heavy)

## Best For

- triax enthusiasts

## Why This Product

- Trusted triax brand quality
- Free international shipping included
- Worldwide delivery with tracking
- 15-day hassle-free returns

## Key Features

- • **Fuel Efficiency Boost:** Gain 4-6% better MPG—save money and reduce your carbon footprint on every mile.
- • **Extended Drain Intervals:** Go beyond 100,000 miles on highway trucks—less downtime, more road time.
- • **Unmatched Engine Longevity:** Up to 48% less wear with Moly-Boron friction modifiers for bulletproof durability.
- • **Injector Stiction Eliminated:** Built-in HEUI injector protection means zero lockups and zero extra additives.
- • **Extreme Cold Start Reliability:** Starts smoothly down to -45°F, ensuring your diesel powers up in any climate.

## Overview

Triax Fleet Supreme 15W-40 is a full synthetic, API CK-4 certified heavy-duty diesel engine oil enhanced with Moly and Nano-Boron friction modifiers. Designed for superior wear protection, it delivers up to 48% less engine wear and improves fuel economy by 4-6%. Engineered for extreme cold starts down to -45°F and extended drain intervals exceeding 100,000 miles, it ensures peak performance and durability for heavy-duty diesel trucks from Ford, Chevy, Dodge, and more. This USA-made oil also eliminates HEUI injector stiction and protects diesel particulate filters, making it a top-tier choice for professional-grade diesel engine care.

## Description

Buy Triax Fleet Supreme 15W-40 API CK-4 Full Synthetic Heavy Duty Diesel Engine Oil | Moly Boron Friction Modified | Extended Drain (5 Gallon): Motor Oils - desertcart.com ✓ FREE DELIVERY possible on eligible purchases

Review: Very good oil made in USA not some garbage from china - Great oil my powersmoke idles way smoother and cold starting is a ease 8 to 10 degree difference cooler oil temperature
Review: Triax is a Top Shelf motor oil - I've been running this in my 2020 f250 6.7l for 5 yrs now. I also use Triax in all my other vehicles as well as farm tractor and lawn mower. Their grease is also a great product. I even have neighbors using Triax as well, and to top it off they are out of Houston TX and a USA made Company which makes purchases more honorable! They are definitely a top shelf quality profuct.

## Features

- WHY TRIAX: Quieter engine operation, lower operating temperature, 4-6% MPG Improvement, faster and smoother turbo spooling, exceptional cold start properties down to -45 F. Outperforms leading brand motor oils by a wide margin.
- FRICTION MODIFIED: Boosted with Nano-Boron and Moly friction modifiers for significantly improved wear protection over any other diesel engine oils. EXTREME WEAR Protection - Up to 48% lower wear than learning OEM and industry standards due to a much lower friction coefficient (50% lower or better) than the competition.
- IDEAL FOR DIESEL PICK-UP TRUCKS: Full compatibility with any heavy duty diesel trucks from Ford Powerstroke, Chevy Silverado, Dodge RAM, GMC Sierra, and many others.
- LONGEST DRAIN INTERVALS: Capable of drain intervals exceeding 100,000 miles for highway trucks (semis) and 30,000 miles Super Duty Pickups.
- IMPROVED DURABILITY: Very high shear stability and film strength. Maintains its viscosity better than other diesel oils. Protects your engine in severe service conditions such as towing or hauling, without compromising drain intervals.
- ELIMINATES STICTION: The only engine oil that eliminates HEUI injector stiction, preventing injector lockup, engine misfires, and a lot of headaches; No need to use additional aftermarket additives Everything you need is built in and fully optimized for unmatched performance.
- DPF / SCR PROTECTION: Keeps your diesel particulate filters clean, prevents clogging and maintains engine optimal functionality. FULLY COMPATIBLE with all heavy duty CK-4 or previous diesel engines, including Volvo, Cummins, Detroit Diesel, MAN, Scania, Powerstroke, and Duramax.

## Technical Specifications

| Specification | Value |
|---------------|-------|
| ASIN | B0163GRIUY |
| Best Sellers Rank | #57,242 in Automotive ( See Top 100 in Automotive ) #437 in Motor Oils |
| Brand | Triax |
| Brand Name | Triax |
| Compatible with Vehicle Type | Heavy Duty Diesel Trucks & Equipment (API CK-4) |
| Container Type | Pail |
| Customer Reviews | 4.7 out of 5 stars 398 Reviews |
| Item Weight | 39 Pounds |
| Liquid Volume | 5 Gallons |
| Manufacturer | Triax Lubricants LLC |
| Manufacturer Part Number | F946 |
| Package Information | Pail |
| UPC | 852771008002 |
| Unit Count | 640 Fluid Ounces |
| Vehicle Service Type | Heavy Duty Diesel Trucks & Equipment (API CK-4) |
| Viscosity | 15W-40 |

## Product Details

- **Viscosity:** 15W-40
- **Brand:** Triax
- **Vehicle Service Type:** Heavy Duty Diesel Trucks & Equipment (API CK-4)
- **UPC:** 852771008002
- **Automotive Fit Type:** Universal Fit

## Images

![Fleet Supreme 15W-40 API CK-4 Full Synthetic Heavy Duty Diesel Engine Oil | Moly Boron Friction Modified | Extended Drain (5 Gallon) - Image 1](https://m.media-amazon.com/images/I/715WJaL8jPL.jpg)

## Available Options

This product comes in different **Size** options.

## Questions & Answers

**Q: Dear triax when ru guys going to start selling your full syn 80/90 gear oil 5gal buckets on amazon? wanting to change oil in the  trans and rear ends**
A: Hello, we do not have an 80W90 synthetic, the only synthetics are 75W90 500k mile oil, SAE 50 and SAE 75W140.  Given all else being equal, 75W90 has significant benefits over 80W90 as it provides probably 3-4% better fuel economy. The viscosity is virtually the same (not much difference). 

The 80W90 is here: https://www.amazon.com/dp/B07BTN2PTL
The 75W90 synthetic is here: https://www.amazon.com/dp/B06XGL7WGZ

**Q: Can someone share oil test results from independent lab? i've noticed oil is not api certified nor mentioned as approved oil in mfg specifications**
A: Hello,

The lubricants we make, with a few exceptions, are not API approved because we do not make cookie cutter formulations. API generally only approves "preset / generic" formulations which are a far cry from what is actually possible performance wise. In order to have API approve any modified formulations, it will cost the manufacturer literally millions of dollars. API is a company, like any other business, in it for the money.  Our oils are very heavily modified especially with regards to friction reduction, oxidation and wear, far beyond standard API cookie cutter formulations, so we are not really interested in this type of "classification". 99% of the oils you buy out there with API license are the same exact 2 or 3 formulations, packaged under hundreds of different brands.

Truth be told, API standards are really not that great when compared to a lot of OEMs, such as VOLVO VDS-4, MAN 3575, VW 507, etc. 
All the tests you see on the spec sheet and product info sheet are validated by third party lab tests. We use at least 2 other labs to verify our own in house testing for each product.

With respect to OEM specs, each oil adpack comes with its own OEM credentials attached. These are based on performance criteria set by OEMs and known generally as “specs”.  This guarantees OEM compliance. However, to get an OEM certification or approval, to have an OEM put your product on their website (formal approval), every oil manufacturer has to pay them separately for each spec and each product . This is essentially a substantial marketing fee. (performance is already approved through the adpack manufacturer).  Needless to say, this significantly changes the  cost of the finished oil and the cost to you, unless one is willing to use a pre-approved cookie cookie-cutter formulation, which we will not. 

That being said, every product we have is backed by a 2 million USD warranty / guarantee against the specs and applications on the product data sheet. We also have 99% customer retention and an exceptional performance track record. Every user is free to test the oil as they see fit. I think our products will change your definition of “Quality”. 

Regards,
Martin
TRIAX Lubricants Tech Group

**Q: is this ok for cummins ISB 275 in a motorhome**
A: On the third photo there is a list of requirements the oil meets, one of them is the Cummins CES 20086 which is the latest standard Cummins has issued and per this link it meets or exceeds all the needs of older Cummins engines http://www.imakenews.com/lubritec/e_article003449158.cfm?x=b11,0,w .  I am currently running this oil in my 5.9 305hp Cummins and plan on having an oil analysis done next year to see how well it holds up.

**Q: How is this for John Deere compact utility tractors? Have a 3320, a 3720 w/turbo, and a gator w/diesel, looking for a one size fits all solution…**
A: It should work exceptionally well.

## Customer Reviews

### ⭐⭐⭐⭐⭐ Very good oil made in USA not some garbage from china
*by P***R on January 3, 2026*

Great oil my powersmoke idles way smoother and cold starting is a ease 8 to 10 degree difference cooler oil temperature

### ⭐⭐⭐⭐⭐ Triax is a Top Shelf motor oil
*by L***R on January 8, 2026*

I've been running this in my 2020 f250 6.7l for 5 yrs now. I also use Triax in all my other vehicles as well as farm tractor and lawn mower. Their grease is also a great product. I even have neighbors using Triax as well, and to top it off they are out of Houston TX and a USA made Company which makes purchases more honorable! They are definitely a top shelf quality profuct.

### ⭐⭐⭐⭐⭐ Gotta say I'm happy with the performance of this oil
*by M***L on April 28, 2017*

Gotta say I'm happy with the performance of this oil, which I noticed when I first used it on my own F250 prompting me to switch all of our semi trucks on it. We used to run Rotella and Royal Purple on 8 long haul trucks. I've been using this oil in my trucks for about a year and a half, buying it from Ebay, and now happy to see is on Amazon Prime which is convenient for me. Performance: I had instant startup at -20F freezing temp after being left outside all night so great cold start performance, havent gotten that with other 15w40's, mostly used Royal purple until now but product seems to perform much better. For my truck (F250), had it analyzed at 10k and then 15k miles. Changed changed the oil at 15250 miles even through Polaris labs came back with green across the board. Additive depletion was less than 15-20% vs fresh oil, which is very good. Probably could have gone to 20 or 25k without issues but 15k miles is enough. Our highway semis regularly run 75-90k miles without a bypass filter. Started them out at 45k drain then gradually increased to current level. Oil analysis comes back green at 70k highway miles. TBN seems to stay at safe levels all the way through, without any TBN boosters. The viscosity also stays within the spec range of a 15W-40 all the way through, doesnt get thicker or thinner. This saves us additional cash as we dont need to use oil viscosity stabilizers. When we used other brands of oil, after about 30k miles the viscosity would drop and we had to use Lucas oil stabilizers to "thicken it up". High quality product, great price and highly recommended. Will keep using it.

## Frequently Bought Together

- Triax Fleet Supreme 15W-40 API CK-4 Full Synthetic Diesel Engine Oil | Friction Optimized and Boosted with Molybdenum & Nano-Boron | Superb Powerstroke Performance (5 Gallon)
- Motorcraft- Oil Filter
- Triax Fleet Supreme 5W-40 ESP API CK-4 Full Synthetic Diesel Engine Oil, Friction Optimized and Boosted with Molybdenum and Nano-Boron, Superb Powerstroke Performance (5 Gallon)

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*Product available on Desertcart Iceland*
*Store origin: IS*
*Last updated: 2026-03-12*