Engine Degreaser vs Dish Soap: Which One Should You Buy?

A greasy engine bay makes every job under the hood messier. Engine degreaser vs dish soap is the question when the bottle on the shelf is a kitchen staple and the parts store holds a foam made for engines. This comparison covers both sides, then two examples of each side from the listings reviewed.

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#	Product	Shop Score	Buy
1	Gunk Engine Cleaner – Foamy Spray for Engines	9.6/10	Buy on Amazon
2	Chemical Guys, Citrus Degreaser Aerosol	9.6/10	Buy on Amazon
3	Dawn Ultra Dish Soap Refill Jug	9.4/10	Buy on Amazon
4	Dawn Original Dish Soap Liquid Dishwashing	9.4/10	Buy on Amazon

1

Gunk Engine Cleaner – Foamy Spray for Engines

Gunk·9.6/10 Shop Score

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The Shop Score runs from 9.2 to 9.8 and weighs performance (35%), build (25%), value (25%), safety (10%, where it applies) and warranty (5%), using only what the manufacturer and the listing publish. How we pick ›

An expanding foam engine cleaner in a 17 oz pack of 2, made for engines with plastic covers, that clings to vertical surfaces and rinses off with a hose.

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Pros

• Expanding foam clings to vertical surfaces and works into crevices
• Stated safe on plastic covers, under-hood rubber and paint
• Removes oil, dirt and road grime after 10 to 15 minutes, then rinses with a hose
• Listed for cars, trucks, mowers, RVs, ATVs and farm equipment

Cons

• No warranty term is stated
• Needs a hose and 10 to 15 minutes before rinsing
• Sold as a pack of 2 only; no single can is listed
• Only one size is listed: 17 oz in a pack of 2

2

Chemical Guys, Citrus Degreaser Aerosol

Chemical Guys·9.6/10 Shop Score

i

The Shop Score runs from 9.2 to 9.8 and weighs performance (35%), build (25%), value (25%), safety (10%, where it applies) and warranty (5%), using only what the manufacturer and the listing publish. How we pick ›

An industrial-strength citrus aerosol degreaser in an 18 oz pack of 2, for engines, tools and undercarriage components.

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Pros

• Industrial-strength citrus formula for heavy grease, oil and grime
• Pressurized spray reaches tight spaces, bolts, brackets and hinges
• Pack of 2 covers multiple vehicles or large cleaning jobs
• Listed for engines, tools, garage floors and work tools

Cons

• Warranty is 30 days through Amazon only
• No dwell time is stated
• No plastic-cover safety statement is given
• Aerosol format only; no refill option is listed

3

Dawn Ultra Dish Soap Refill Jug

Dawn·9.4/10 Shop Score

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The Shop Score runs from 9.2 to 9.8 and weighs performance (35%), build (25%), value (25%), safety (10%, where it applies) and warranty (5%), using only what the manufacturer and the listing publish. How we pick ›

A concentrated dish soap in a 51.5 oz refill jug with an easy-pour spout, made for dishes, with grease-fighting power for dishes.

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Pros

• Concentrated formula; a little goes a long way for dishes
• 51.5 oz refill jug fills multiple standard bottles
• Easy-pour spout and comfortable handle for refilling
• Maker states Dawn is the #1 dishwashing liquid brand in North America

Cons

• Made for dishes, not for engines; no engine use is stated
• No dwell time or rinse guidance for an engine bay
• Bullets describe Dawn Platinum, not the Dawn Ultra in this listing
• No warranty term is stated

4

Dawn Original Dish Soap Liquid Dishwashing

Dawn·9.4/10 Shop Score

i

The Shop Score runs from 9.2 to 9.8 and weighs performance (35%), build (25%), value (25%), safety (10%, where it applies) and warranty (5%), using only what the manufacturer and the listing publish. How we pick ›

A 38 oz bottle of original dishwashing liquid, made for dishes, with grease-fighting power for dishes.

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Pros

• Breaks down grease for dishes, per the listing
• Blue liquid dishwashing detergent, as listed in the spec table
• 38 oz bottle, pack of 1
• Maker states it is the #1 dishwashing liquid brand in North America

Cons

• Made for dishes, not for engines; no engine use is stated
• Bullets describe Dawn Ultra, Dawn Platinum and EZ-Squeeze, not this Original bottle
• No dwell time or rinse guidance for an engine bay
• No warranty term is stated

Side by side

Specs such as CFM, PSI and torque are the manufacturer’s ratings as listed, collected 12 November 2026.

Engine degreaser vs dish soap: how each side cleans

An engine degreaser breaks down grease, oil and road grime on engines and tools. The Gunk foam is made for engines with plastic covers, and the Chemical Guys aerosol is an industrial-strength citrus cleaner for engines and tools. Dish soap is made for dishes: both Dawn listings describe grease-fighting power for dishwashing. A bullet in each listing mentions greasy tools and car wheels, but it names Dawn Platinum, not the Dawn Ultra or Dawn Original in these listings. That is the split: one side is built for the engine bay, the other is a kitchen cleaner made for dishes.

Foam, cling and dwell time

The Gunk foam expands after spraying, clings to vertical surfaces and works into crevices, then rinses off with water after 10 to 15 minutes. The Chemical Guys aerosol is a pressurized spray that reaches tight spaces, bolts, brackets and hinges, and it begins dissolving grease on contact. Neither Dawn listing states a dwell time or a foam that clings, because dish soap is a liquid made for a sink. Where grime sits in crevices, the Gunk foam has the stated advantage.

What each side is made for

Gunk states its foam is safe on plastic covers, under-hood rubber and paint. Chemical Guys lists cars, trucks, SUVs, motorcycles, off-road vehicles, shop equipment and work tools. Dawn Ultra is a refill jug for dish soap bottles and Dawn Original is a bottle of dishwashing liquid; both point to dishes first. Neither Dawn listing states it is made for engines or plastic covers, so the engine bay is outside what the dish soap listings promise.

Example cleaners

More choices: the engine degreaser vs brake cleaner, and the car wash soap vs dish soap comparison.

Garage Fit Check

• Gunk foam rinses off with a hose after 10 to 15 minutes, so have a hose ready before you spray.
• Chemical Guys is an 18 oz aerosol in a pack of 2, so two cans cover more than one job.
• Dawn Ultra is a 51.5 oz refill jug, so leave shelf room for the jug.

FAQ: garage tools

Can dish soap clean an engine bay?

Neither Dawn listing states the soap is made for engines or plastic covers. A bullet in each listing mentions greasy tools and car wheels, but it names Dawn Platinum, not the Dawn Ultra or Dawn Original in these listings. Both engine degreasers state they are made for engines and tools.

Is engine degreaser safe on plastic covers?

Gunk states its foam is safe on plastic covers, under-hood rubber and paint. Chemical Guys does not state that safety, and neither Dawn listing states whether dish soap is safe on paint or rubber under the hood.

How long should engine degreaser stay on before rinsing?

Gunk states 10 to 15 minutes, then rinse with a hose. Chemical Guys states its spray begins dissolving grease on contact but gives no dwell time in the listing.

Which side cleans heavy grease better?

Both engine degreasers are made for grease, oil and road grime on engines. Dish soap is made for dishes, and its listings describe grease-fighting power for dishwashing, not for caked-on grease.

Related: the engine degreaser vs brake cleaner comparison, the car wash soap vs dish soap comparison, the best pressure washer for engine bay, and the concrete etch vs degreaser comparison.