Updated April 2026 / National averages

Coolant flush cost in 2026:$100 to $200at most shops

Full machine flush at an independent shop, sourced from labor rate surveys and shop quotes. A drain-and-fill is cheaper, DIY is cheaper still, and a dealer is roughly double.

Drain-and-fill

$50-$100

Gravity drain, ~50% replaced

Full Flush

$100-$200

Machine pumped, ~95% replaced

DIY

$20-$50

Materials only

Coolant Spectrum

Match the colour, mind the chemistry
IATGreen
OATOrange
HOATYellow
PHOATPink
PHOATBlue
  • IAT Pre-2000 US vehicles, 2 yr / 30k mi interval
  • OAT GM Dex-Cool, VW, 5 yr / 150k mi
  • HOAT Ford, Chrysler, many European, 5 yr / 150k mi
  • PHOAT Toyota (pink), Honda and Subaru (blue), 5-10 yr

Never mix types. Inhibitor packages react and form a gel that blocks the heater core.

Service Desk

Coolant Flush Cost Estimator

Live estimate

A drain-and-fill removes about half. A machine flush gets nearly all of it.

Check the owner manual or reservoir cap. Mixing types causes gel and corrosion.

Estimated Total

$92 to $168

Full coolant flush with PHOAT (pink or blue)

Coolant Cost

$22 - $38

Materials only

Labor Cost

$70 - $130

Independent mechanic

Service Interval

5 to 10 yrs

or 100,000+ mi

Save vs dealer

$70

by skipping the dealer

Coolant Replacement

Near-complete (~95%) old coolant removal

How this is calculated

Estimates use 2024-2026 national averages from repair shops, parts retailers, and labor rate surveys. Actual costs vary by region, cooling system capacity, and coolant brand.

Service breakdown

What each service actually does

Full comparison →
ServiceTypical CostCoolant ReplacedTimeBest For
Drain-and-fill$50 - $100~50%20-30 minMaintained systems on schedule
Machine flush$100 - $200~95%45-60 minNeglected systems or coolant type changes
Flush + chemical cleaner$130 - $250~95% + descaler60-90 minVisible scale, brown coolant, blocked passages
Dealer flush (OEM)$200 - $400~95% (OEM coolant)60-90 minWarranty vehicles, European makes
DIY drain-and-fill$20 - $50~50%45-60 minConfident DIYers with the right coolant

Pricing factors

What drives your final number

1 to 2 hours

Labor rate

Shop labor is $70 to $130 per hour for independents, $100 to $180 at dealers. A flush takes about an hour, so labor alone is $70 to $180.

1.5 to 4 gallons

Coolant type and volume

IAT runs $8 to $12 a gallon, OAT and HOAT $15 to $25, OEM Si-OAT for European makes $25 to $35. Trucks need more.

Gravity vs machine

Service method

A machine flush costs more in shop time and equipment but replaces nearly all the fluid. Gravity drain is faster and cheaper but partial.

Dealer vs chain vs indy

Location and shop

Quick-lube chains are the floor at $99. Independent shops cluster $100 to $180. Dealers run $200 to $400 with OEM coolant and full inspection.

Where to get it done

Chain shop and dealer prices at a glance

Full price comparison →

Jiffy Lube

~$99

Exchange

Valvoline

~$99

Exchange

Take 5

$99-$120

Exchange

Pep Boys

$120-$160

Machine flush

Midas

$120-$170

Machine flush

Firestone

$130-$180

Machine flush

Independent

$100-$180

Varies

Dealership

$200-$400

OEM flush

Pricing reflects 2026 published rates and shop quote averages. A 10-minute phone round across three shops typically saves $50 to $80.

Why service is needed

Coolant degrades with every heat cycle

Coolant is not just water and dye. It carries a package of corrosion inhibitors that protect aluminum, iron, copper, and rubber inside the cooling system. Those inhibitors deplete with use. Once they are gone, the coolant turns mildly acidic and starts attacking the metal it was supposed to protect.

Heat cycles, contamination from dissolved minerals, and small amounts of combustion gas pushed past the head gasket all accelerate the breakdown. Hot climates and stop-and-go driving make it worse. Towing and hauling stress the system further.

Fresh coolant

  • + pH 8 to 11, slightly alkaline
  • + Active inhibitors coat metal surfaces
  • + Clean, transparent fluid
  • + Heat transfer at design specification

Old coolant

  • ! pH below 7, mildly acidic
  • ! Inhibitors depleted, metal exposed
  • ! Brown or rust-coloured, murky
  • ! Scale deposits restrict flow

Engine coolant temperature

Operating window
Cold startNormal 195-220°FOverheat

When the gauge climbs past normal on a route the vehicle used to handle easily, blocked passages from scale and depleted inhibitors are reducing flow. Flush before a thermostat or water pump fails.

Critical safety note

Never mix coolant types

Mixing IAT (green) with OAT (orange) is the most common mistake. The silicate inhibitors in green react with the organic acids in orange and form a gel that blocks the heater core, the thermostat housing, and narrow radiator passages. The damage is real, the repair is expensive, and a single bad fill can cost more than ten years of correct service.

Modern vehicles often need OEM-spec coolant. A Toyota wants pink SLLC, a Honda blue Type 2, a Mercedes purple Si-OAT. Universal yellow is fine for emergency top-offs but not for the actual flush on those vehicles. Verify the spec, not the colour.

Coolant type lookup →
IAT + OATGel formation, heater core blocked
IAT + HOATReduced inhibitor protection
OAT + HOATInhibitor degradation, reduced life
Same type, different brandGenerally fine if spec matches

Common questions

Coolant flush FAQ

How much does a coolant flush cost?

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A full coolant flush costs $100 to $200 at most shops. A drain-and-fill costs $50 to $100 but only replaces about half the fluid. DIY runs $20 to $50 in materials. Dealers charge $200 to $400, especially for European vehicles requiring OEM-spec coolant.

How often should you flush coolant?

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It depends on the coolant type, not a single number. Older IAT (green) coolant needs replacing every 2 to 3 years or 30,000 miles. Modern OAT, HOAT, and PHOAT coolants last 5 to 10 years and 100,000 to 150,000 miles. Toyota, GM, Honda, and Subaru each have different intervals.

Can you mix green and orange coolant?

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No. Mixing IAT (green) with OAT (orange) causes the inhibitor packages to react and form a gel that blocks the heater core, thermostat housing, and narrow radiator passages. If types have already been mixed, a full machine flush is required, not a drain-and-fill.

What is the difference between a coolant flush and a drain-and-fill?

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A drain-and-fill opens the radiator petcock and lets gravity remove what it can, replacing about 50 percent of the fluid. A machine flush connects to the cooling system and pumps new coolant through under pressure, replacing 90 to 95 percent. The flush takes 45 to 60 minutes versus 20 to 30 for a drain-and-fill.

Can you do a coolant flush yourself?

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Yes, a drain-and-fill is beginner-friendly and saves $80 to $150. Tools needed: drain pan, basic wrench set, gloves, a flush kit T-adapter, distilled water, and the correct coolant for your vehicle. The trickiest step is bleeding air from the system, which most guides skip. Never pour coolant down a drain.

How long does a coolant flush take?

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A drain-and-fill takes 20 to 30 minutes. A full machine flush takes 45 to 60 minutes. Add 15 to 30 minutes if a chemical descaler is used. Plan to leave the vehicle for an hour at minimum if booking a true cooling system flush.

Updated 2026-04-27