Best Engine Degreasers for Effective and Safe Cleaning in 2025

Engines pick up grease, oil, and dirt over time. That gunk can slow things down and make repairs a pain.

Engine degreasers are made to break up this buildup. They help keep engines cleaner and running better by making grime much easier to rinse away.

Our top pick:

WD-40 Specialist Degreaser

You’ll find water-based, solvent-based, and citrus-based degreasers out there. Each has its quirks—some are tougher on grease, some are gentler on surfaces, and a few are more eco-friendly than others.

Picking the right one means you’re less likely to mess up engine parts or fry any electrical bits. It’s worth thinking about what you need before grabbing just anything off the shelf.

Strength, safety, and chemical content matter a lot. You don’t want something too harsh for your engine, or a hassle to rinse off.

We tried a bunch of products to see which ones actually clean well, aren’t a pain to use, and don’t cause extra problems.

Best Engine Degreasers

We put a variety of engine degreasers to the test, just to see which ones actually do the job. The products below hit the sweet spot: strong enough to clean, but not so harsh they’ll wreck your engine.

Pick one that matches what you need—there’s no single “best” for everyone, but these are all solid options.

WD-40 Specialist Degreaser

This one’s great for deep cleaning engines and machinery without leaving a mess behind.

Pros

• Foam tackles tough grease fast
• Nozzle sprays up to 5 feet—pretty handy
• Doesn’t leave much residue

Cons

• Foam sometimes takes a while to rinse off
• Smells a bit chemical, not scented
• Nozzle might need a little fiddling

We sprayed this WD-40 degreaser on a greasy engine and the foam stuck right where we needed it. It worked into cracks and broke down dirt better than a lot of sprays we’ve used.

The long spray reach made it easier to hit awkward spots. Cleaning felt faster because the foam didn’t drip everywhere—nice bonus.

Sometimes it needed extra water to rinse off, and the nozzle took a bit of adjusting. But if you want a strong cleaner that’s easy to use, especially in tight places, this one’s worth a look.

Simple Green Pro HD Engine Degreaser

This cleaner is a solid pick if you want something that handles a bunch of tough jobs—not just engines.

Pros

• Gets rid of grease without a nasty smell
• Safe for metals and lots of surfaces
• Biodegradable, pro strength

Cons

• Needs more elbow grease on really thick gunk
• Purple color is a bit odd at first
• Spray bottle runs out quick on big jobs

We tried Simple Green Pro HD on engines and even grills. It cleaned well and didn’t leave behind strong fumes.

Light to medium grime came off fast, but heavy buildup sometimes needed a second pass or a little scrubbing. The purple color looks strange, but it works fine.

Simple Green Industrial Cleaner and Degreaser

This one’s handy for tough cleaning around the house or workshop, and it’s safe to use pretty much anywhere.

Pros

• Handles grease without harsh chemicals
• Non-toxic and biodegradable
• Can be diluted to fit the job

Cons

• Needs some scrubbing on stubborn dirt
• Big bottle can be awkward to store
• Not as heavy-duty for the worst grime

We used this cleaner on engine parts and around the garage. It got rid of grease better than a lot of others, and didn’t stink up the place or leave any weird residue.

Being able to dilute it was a nice touch—it saved us money and worked fine for lighter jobs. It rinsed off easily, too.

For old, caked-on grime, it’s not a miracle worker, but for regular cleaning, it’s reliable and lasts a while.

WD-40 Specialist Industrial-Strength Degreaser

This degreaser works fast on tough engine grease and heavy machinery. It’s good for both pros and DIYers.

Pros

• Fast on thick grease
• Safe for plastics and metals
• Smart Straw for precise or wide spray

Cons

• Strong scent—open a window!
• Can leave a slight residue
• Spray nozzle is kind of powerful

We found it broke down grease quickly without harming rubber or plastic. Cleaning engine blocks and tools was definitely easier.

The Smart Straw is useful for getting into small spots or spraying wide. The smell is pretty strong, so we always used it outside.

Sometimes it left a thin film that needed wiping off, but overall, it’s a dependable pick for tough jobs.

3D Grand Blast

If you want a tough, fast-acting degreaser that’s safe on a bunch of surfaces and easy to rinse, we really like the 3D Grand Blast.

Pros

• Hits heavy grease and grime hard
• Safe for metal, plastic, paint, and rubber
• Biodegradable and better for the environment

Cons

• Might be overkill for small jobs
• Costs a bit more than basic formulas
• Needs a thorough rinse to avoid residue

When we tried 3D Grand Blast, it chewed through old engine grease with barely any effort. Wheel wells and exhaust tips came out clean, and nothing got damaged—not even the paint or rubber.

No harsh smell or sticky leftovers, either. We rinsed everything off pretty easily, even without a power washer.

It’s made in the USA and seems to care about the environment, which is a nice bonus. If you want a cleaner that’s strong but not scary, this one’s a safe bet.

Buying Guide

When we’re picking an engine degreaser, we care most about effectiveness and safety. It’s got to get rid of grease fast without messing up parts or paint.

It’s a bonus if it works on rubber, plastic, and metal too. Products that are easy to spray on and rinse off save time and headaches.

Environmental impact is a big deal for us. We always check if it’s biodegradable or skips any nasty chemicals—better for you and the planet.

Drying time matters as well. Some degreasers dry super fast, others need more water or time, which might delay getting your car back on the road.

Features to Compare

Feature	What to Look For	Why It Matters
Cleaning Power	Strong enough to remove all grease	Saves time and effort
Material Safety	Safe for all engine parts	Prevents damage to engine components
Application	Spray, gel, or liquid form	Can make cleaning easier—or honestly, sometimes just messier
Rinsing Needed	Whether requires water	Impacts cleanup time and how much hassle you’re in for
Environmental Impact	Biodegradable or eco-friendly	Better for both people and the planet
Drying Time	Fast or slow	Let’s face it, faster drying is ideal if you’re in a hurry