Instant Online Pricing
Nationwide Delivery
Drums, Totes & Tankers
Technical Support
How The Oil Store Works
1
Enter ZIP & Gallons
Start by entering your delivery ZIP code and the number of gallons needed.
Our system instantly calculates delivered transformer oil pricing based on real freight routes and available supply locations — no account or contact info required.
2
Review Delivered Pricing
Compare pricing by oil type and packaging, including drums, totes, and tanker loads.
All prices shown include freight to your location, allowing you to quickly evaluate the best option for your project.
3
Schedule Delivery
& Checkout
Select your delivery address and preferred delivery date, then complete checkout using credit card, ACH, or Net-30 terms for approved accounts.
Orders are confirmed immediately based on real availability.
Get oil delivery confirmation in minutes — not days.
Get started and see up-front prices
Transformer Oil for Every Application
Mineral, natural ester, and synthetic ester dielectric fluids —
available in drums, totes, and full tanker loads.
Mineral Insulating Oil
Lowest Cost / Widest Use
ASTM D3487 Type II inhibited mineral insulating oil — the most widely used dielectric fluid in the power industry. Engineered for use in power and distribution transformers, circuit breakers, tap changers, and switchgear, mineral oil provides proven electrical insulation and heat dissipation at the lowest cost per gallon of any transformer fluid.
Our mineral oil meets or exceeds ASTM D3487 Type II specifications for dielectric breakdown voltage, oxidation stability, pour point, and interfacial tension. Inhibited with oxidation stabilizers to extend service life and reduce maintenance intervals compared to Type I uninhibited oils.
Available in 55-gallon drums, 330-gallon totes, and full tanker loads up to 6,500 gallons. All shipments include certificates of analysis and conform to IEEE C57.106 guidelines for oil acceptance and maintenance.
Natural Ester Fluid
Biodegradable / High Fire Point
Natural ester transformer fluid is a vegetable-based dielectric coolant designed as a high-performance, environmentally responsible alternative to conventional mineral oil. With a 330°C flash point — nearly three times that of mineral oil — natural ester virtually eliminates transformer fire risk and is increasingly specified for indoor installations, urban substations, data centers, and environmentally sensitive locations.
Beyond fire safety, natural ester fluid extends insulation paper life by 5–8x compared to mineral oil by absorbing moisture from the cellulose insulation system. This translates directly to extended transformer service life and reduced end-of-life asset replacement costs. Natural ester is fully biodegradable and non-toxic, meeting EPA requirements for environmentally acceptable lubricants.
Available in 55-gallon drums, 330-gallon totes, and tanker loads. Compatible with new transformer fills and retrofill applications where existing mineral oil is replaced in the field.
Synthetic Ester Fluid
Cold Climate / High Performance
Synthetic ester is a polyol-ester based engineered dielectric fluid designed for high fire safety, extended temperature range, and superior oxidation stability. With a pour point as low as -56°C and a flash point above 250°C, synthetic ester operates reliably in extreme cold climates where both mineral oil and natural ester face performance limitations.
Synthetic ester is fully miscible with both mineral oil and natural ester, making it the most versatile option for retrofill projects where complete fluid removal isn't practical. It's widely specified for traction transformers in rail applications, mobile transformers, and critical-use installations where both fire safety and cold-weather reliability are required.
Available in 55-gallon drums and 330-gallon totes. All shipments include full test documentation and certificates of analysis.
Why TransformerParts.com
Built for the way utility crews, contractors, and engineers actually buy.
Instant Pricing, No Sales Process
See your exact delivered cost in seconds. No forms, no phone calls, no waiting for a rep to get back to you.
Largest Distribution Network
See your exact, competitive, delivered price in seconds. Our unique network of distribution centers and carriers enables us to provide strong prices to users.
Every Oil Type & Unitization
From a single 5-gallon pail for a spot replacement to a 6,500-gallon tanker for a fleet refill — order the quantity your project needs.
Engineering Expertise
Founded by electrical engineers with hands-on transformer experience. We understand your specs, your standards, and your deadlines.
Flexible & Modern Payment
Pay by credit card or ACH at checkout, or apply for Net-30 terms for approved accounts.
Transformer Components & Accessories
Monitoring instruments, breather desiccant, cable entrance plugs, oil level indicators, temperature gauges, pressure relief devices, cooling fans, and more — from manufacturers including MESSKO and Incon. All products ship with full technical documentation and engineering support.
Don't see the part you're looking for? Request it and we will add it to our store. Our store is forever expanding.
Who We Are
TransformerParts.com was founded by an electrical engineer and power equipment sales professional who saw the need to modernize how utilities, contractors, and maintenance teams buy transformer oil and components. We combine the technical knowledge of a traditional distributor with the speed and transparency of modern e-commerce — instant pricing, online ordering, and engineering support when you need it.
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