- Direct Supplier of Diesel and Critical Fluids
- Fuel Quality Protected and Guaranteed
- Complimentary Support and Delivery Services
- 24/7 Emergency Delivery Services
Fleet Core Knows Fuel and the Front Range Conditions That Test It
Managing fuel in Colorado is its own challenge. Altitude matters. Temperature swings matter. A hard freeze in February followed by a 70-degree day in March can mean the difference between diesel that flows and diesel that gels. Fleet Core has spent years working with Colorado operations across construction, agriculture, municipal fleets, and critical facilities. That experience shows up in every delivery and every service call.
We don’t show up with a generic contract. We look at how you use fuel, where you store it, and what your equipment demands. From there, we build a program that fits. That might mean scheduled bulk delivery with reporting by vehicle. It might mean quarterly fuel polishing for your generator tanks. It might mean an oil analysis program for your farm equipment before planting season. Whatever the mix, the goal is the same: no surprises, no downtime, no scrambling.
Your Complete Source for Fuel Delivery, Storage, and Quality
Fleet Core is a direct fuel supplier serving Windsor and the broader Weld County corridor. We’re not a broker. We handle diesel delivery, essential fluid programs, and the technical services that keep stored fuel and working equipment in top condition. Whether you manage a construction fleet, a hospital generator bank, or a large farm operation, we have the delivery schedule and the expertise to keep things moving.
Fuel Delivery
On-road clear diesel, off-road red-dyed diesel, and emergency fuel delivered directly to your site. Scheduled or on-call.
Fuel Testing
Know what’s in your tanks before it reaches your engines. We test for water, microbial growth, and contamination so problems get caught early.
Fuel Polishing
Stored diesel degrades over time. Fuel polishing removes water, sludge, and particulates to restore fuel quality and protect the equipment it feeds.
Tank Cleaning
Sludge and sediment at the bottom of a storage tank are slow-moving problems. Tank cleaning removes the buildup before it migrates into your fuel supply.
Oil Analysis
Engine oil tells a story about what’s happening inside your equipment. Our oil analysis program flags wear metals, contamination, and fluid breakdown before failure happens.
Petro Buster Petroleum Cleaner & Degreaser
Spills happen. Petro Buster is an eco-friendly petroleum cleaner and degreaser built for real-world cleanup. Have it on hand before you need it, not after.
Our Value
Confidence. Control. Continuity.
Protect Your Equipment With Our Essential Fluid Services
Colorado businesses demand high performance — Fleet Core Essential Fluid Services support dynamic operational conditions.
Lubrication
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Lubrication
- Lubricate engine components
- Minimize friction
- Prevent damage from metal-on-metal contact
Cooling
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Cooling
- Cool engines
- Absorb heat
- Prevent breakdown and failure
Washer Fluid
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Washer Fluid
- Crystal clear operator vision
- Vehicle safety
- Winter operations protection
Emissions Compliance & Performance
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Emissions Compliance & Performance
- Improve performance
- Eliminate smog and illness
- Maintain regulatory compliance
Testimonials
Our Commitment To Excellence
Fleet Core is more than just a fuel and fluid provider — we are your comprehensive ENERGY PARTNER supporting operational reliability, productivity, and sustainability.
“Great company and great service!! Employees are well trained and very professional!!”
“Fleet Core offers excellent customer service. They complete the commitments they make and take care of their clients.”
“Great Diesel and Service. Extremely low temps and Core Power didn’t let me down. I would recommend Fleet Core and Core Power diesel to anyone in the Denver area.”
“Quick and efficient on-site fuel delivery.”