Car Bibles is reader-supported. When you buy through links on our site, we may earn an affiliate commission. Learn more
No one really enjoys degreasing a car engine. But if you really want to help your engine to perform at its best over the long term then it is a good idea to get under the hood and use a quality engine degreaser.
A clean engine will run better with less chance of gunk and dirty grease clogging the moving parts or air intakes. It’s also easier to maintain a clean engine, and it allows you to spot issues such as oil leaks early and fix them before they become a serious problem.
While there are numerous degreaser products on the market that boast they will leave your engine sparkling clean, choosing the right one can be tough. That’s why we’ve put together this list of the best engine degreasers.
The Best Engine Degreaser
This product really does live up to its name, and it is capable of cutting through all sorts of crud. It can cut it on a wide range of surfaces as well. This is not really a specialist product designed for the automotive world. Instead this is a cleaner with an exceptionally wide range of applications – one of which is degreasing engines. Not only can it clean grease & oil, it also works to clean up glue, markers and crayon, paint and tape residue, for example.
It’s also a very mild product that’s water based and biodegradable, and it contains no petroleum solvents, bleach or ammonia. You get a gallon for a great price, but some people may prefer a more specialized, dedicated degreasing product.
Very Wide Range of Applications
Removes a Number of Containments
Biodegradable & Water Based
- BrandKrud Kutter
- Weight8.95 Pounds
The crystal in the name refers to the fact that this product is crystal clear both in appearance and odor. This makes it stand out from Simple Green’s other line of cleaning products, many of which are, surprise surprise, green in color.
This means that this product lends itself very well to degreasing an engine where you really don’t want a range of containments – such as color dyes – hanging around. Instead, this product is non-toxic, biodegradable, non-hazardous, non-corrosive and non-flammable.
It is however a very effective degreaser and cleaning product, which will really get to work on your engine. It’s highly concentrated too, so you can dilute it in your spray bottle before application. That helps the product stretch a little further given the pretty high price tag.
Fragrance & Color Free
Non-Toxic and Biodegradable
- BrandSimple Green
- Weight9 lbs
Is it a bird? Is it a plane? No, it’s Super Degreaser! If you’ve been on Car Bibles for a while you know we question any product that comes at us with some bold claim in the product name. However, when that product also comes from a highly reputable manufacturer like Meguiar’s, then we sit up and take notice.
This product is all about the powerful degreasing action. It is a unique formula specifically designed to tackle even the toughest grease, working hard to break it down so you simply rinse it away with a good stream of clean water.
It’s also specially formulated to be residue free, so after rinsing you won’t be left with any streaks or white marks – an important feature if you really want a sparkling engine you’ll be proud to show off.
It does have a strange herbal fragrance. Some people don’t like it, some people do, and many don’t even notice it, but as a somewhat unique feature it is worth mentioning.
- Weight3.31 lbs
Despite its mildly aggressive name, this product from Oil Eater is actually a remarkably gentle product. It is – deep breath required here – non-toxic, non-corrosive, non-hazardous and even USDA approved for non-food surfaces. It is also acid free and contains no abrasive or petroleum solvents.
That is an impressive list, but don’t let that detract from its main purpose. This product is made for degreasing, and it does that very well, tackling and dissolving all manner of greases and oils.
It’s also safe for use in a wide range of non-car related applications. It can be relied on to safely clean grease and oil stains from all sorts of materials, everything from carpets to asphalt. That makes this an extremely versatile product. It’s highly concentrated, so you can dilute it to suit whatever task you require, and it is a good value too.
Acid Free, Non-Abrasive
Wide Range of Applications
- BrandOil Eater
- Weight8.5 lbs
This product is not a dedicated automobile cleaning product; instead, it is a powerful degreasing (and cleaning) product with a range of applications. You can spray it onto your engine and let it work its magic. It’s non-abrasive, phosphate free and biodegradable, but we suspect it may not be as gentle as some other products on this list.
For example, hidden in the instructions it warns not to use it on plastic or aluminum. That means you need to be very careful when spraying it around your car.
It is very cheap, on the other hand. While it cleans very effectively (and very quickly) just be sure to treat this product with extra care.
Very Low Price
- BrandPurple Power
- Weight8.3 lbs
After a few all-round cleaning products, we now get back to one designed specifically for use on cars, and it is made by one of our favorite brands, Chemical Guys.
This degreaser is not just orange in color for the heck of it. No, Chemical Guys harnessed the natural cleaning power of citrus to develop this powerful cleaner that is formulated to emulsify dirt, grime and oil stains and spills. Once emulsified, the containments can be easily rinsed away with a spray of clean water.
It has a multipurpose element too and is suitable for use all over the vehicle, such as on the undercarriage and even to remove caked-on mud and grime from rims and wheels. It even works on other surfaces, so you can tackle oil stains on your garage floor and bring the sparkle back to your tools.
It’s relatively cheap, but you should note that this price buys you only 16 ounces of product – a relatively small amount since many other products on this list are sold by the gallon. It is very highly concentrated however, so you can dilute it, which adds a bit more value.
Citrus Based Formula
Emulsifies Dirt & Grease
- BrandChemical Guys
- Weight1.08 lbs
We love it when a product lives up to its name, which is why the Tough Task Degreaser from SuperClean has made it onto our list. It really is suitable for the toughest tasks because it is industrial-strength degreaser and cleaner. After application it is designed to get to work instantly, and it works to dissolve a wide range of materials such grease, grime, oil and even tar.
At the same time it’s relatively mild since it’s a water-based solution that’s both biodegradable and phosphate free. It’s perhaps not as mild as some of the others on this list but has great cleaning power.
Its also extremely concentrated, so it can be easily diluted (all the way down to 16:1) so you can make the 32-ounce bottle go a very long way.
- Weight2.2 lbs
The good thing about choosing a multi-purpose cleaner is that you know it is going to be mild enough to use on a range of surfaces. That is somewhat understating the abilities of this cleaner and degreaser from Simple Green, which has a phenomenal list of materials it is safe to use on.
That includes painted surfaces, aluminum, polished & stainless steel, chrome, plastic and vinyl (and much more). While you still need to be careful (as this is a powerful cleaning product), you should be able to spray it all over your engine block without having to worry too much about any product blowback coming into contact with any surface it shouldn’t.
It has a wide range of uses in the home, making it extremely cost effective, and the product is non-toxic so you don’t have to worry about the runoff getting onto your lawn when you’re rinsing the car.
Wide Range of Applications
Safe on a Huge Range of Surfaces
- BrandSimple Green
- Weight9.3 lbs
This cleaner from the Chemical Guys lives up to its name since it’s an extremely concentrated and very strong degreasing product. You can dilute it and still get a great cleaning effect, so this gallon of solution should last quite a long time.
It is formulated to tackle baked-on dirt, grime and oil and has also been designed to rinse off without leaving any residue behind. If you’re looking for a product with a deep clean that produces a shiny engine then this could be for you.
It is also safe to use on a range of surfaces on your car, such as tires and wheel wells, though its main power is definitely degreasing. It’s also not cheap, but the fact you can dilute it does help it go a little further.
Heavy Duty Cleaning Product
- BrandChemical Guys
- Weight9.7 lbs
Best Engine Degreaser Buying Guide & FAQ
As promised, that is our list of what we think are the best degreasing products on the market right now. Whilst any one of them will no doubt do a good job for you, which one is going to do the best? Because as we said up top, degreasing the engine is not particularly fun, so you really want to invest in the product that is going to make the job as simple and straightforward as possible.
That’s why we’ve put together this product buying guide and FAQ to talk through all the features to keep an eye out for, and also answer any questions you may have to help you get the most out of your selected product.
Essential Factors to Consider When Selecting the Best Engine Degreaser
Multi-Surface - Take a look at the number of surfaces the product can be used on. If it’s saying that it can be used (or at least is not harmful to) plastics, painted surfaces, etc then you don’t need to be quite as careful when you’re using the product.
Multi-Purpose - Some products are intended just for the car, some are intended for use around the home and garage too. A multi-purpose product will generally be milder so it can work on a variety of surfaces. It is however better value, as you’re getting the ability to clean a wide range of surfaces with one product.
Smell - A petroleum based cleaner is probably going to smell pretty bad, and you may want to invest in a simple dust mask or something to block the odor. At the other end of the scale, some of these products have added perfume to smell nice. Whether this is at all important will depend on you!
Size - This also goes with price. Frankly, there are some bargains on the list, with many products sold in gallon-sized bottle for relatively low prices. How has that low price been achieved however, and will the cheaper options truly match the cleaning power of the premium brands?
Related Post: Best Grease Guns
Types of Engine Degreaser
Broadly speaking there are two types of engine degreaser, and you can find examples of both of them on the list above. They are Petroleum Based degreasers and Water Based degreasers. Both formulas have pros and cons, so do take a quick look at the product type breakdown here – it might help you to decide which product is going to be better for you.
- Petroleum Based - In general, petroleum-based cleaners will usually be cheaper than a water based product. This is because it is naturally a stronger cleaning product, which doesn’t need the high end formulations that are found in water-based versions. They are also very powerful cleaners, but they can be more abrasive than the water based solutions so you need to be careful when applying them and wipe away any run off or splash back that sprays onto painted surfaces, plastics, chrome and aluminum (unless the product specifically states it is safe on these surfaces).
- Water Based - A degreaser with a water base will naturally be that much gentler and milder than petroleum based versions. They can also be just as effective a cleaning agent, though they will often boast a more high tech formulation to tackle grease and oil than the raw muscle power of petroleum based products. They are going to be milder to use on a range of surfaces, meaning that you won’t have to panic quite so much if the product comes into contact with other surfaces on the car – many products are in fact designed to clean them too. They will usually be more environmentally sound too, so you don’t have to worry about run-off damaging your lawn. The downside is they usually carry a higher price tag.
There is a third type as well, which is the foaming engine degreaser. However, the two types we mentioned above, whilst having a few differences are at least similar in how they are applied and used. A foam based cleaner is quite different, and there exist enough of that type that it really does warrant its own guide – which, if you’re very lucky, we’ll make for you one day.
Engine Degreaser FAQ
Have any questions either especially about degreaser products, or the related topics of cleaning your engine? Well, you’re in luck friend, because this is our section all about Frequently Asked Questions when it comes to Engine Degreasers.
Q: What is In Degreaser?
A: There are a quite a range of ingredients in a degreasing product, and each one will have a slightly different mixture. Even where they share ingredients, they will often be in slightly different quantities across the various brands.
Broadly speaking however these products contain some kind of agitator that works to break down the grease, oil and dirt as well as a solution (normally either petroleum or water based) into which the agitating ingredients are suspended.
The cleaning ingredient(s) differ from product to product and are often a closely guarded secret held by each manufacturer. In our list above you can see some products that include an Emulsifying agent to quickly break down grease and oil and make them easy to wash away. We even have a product that uses Citrus as it’s cleaning agent. Each manufacturer may not specify exactly what the cleaning agent is, but broadly speaking they all perform the same function.
Q: What is Engine Detailing?
A: Remember when you were a kid and your Mom told you to clean your room and you just stuffed everything into the closet and played Playstation instead? That is the same as taking your car to an automatic washer. It looks clean, but it’s only really touching the surface.
Remember when she caught you stuffing your dirty laundry and old toys into the closet, and you spent a summer afternoon filling up garbage bags with crap? That is a level of deep and long lasting cleaning equivalent to engine detailing.
Engine detailing is a very deep clean of the engine block that requires time and tools – but it is worth it for the end results. Here is a nice man with a ponytail to explain further.
Q: Is Degreaser Harmful?
A: Yes, if use it as a mixer in a cocktail.
No, if you follow the instructions. Depending on the type of product you’ve gone for, there will be some materials it is safe to come into contact with and some it is not. Read the instructions on the product you buy and everything will be fine.
Q: What Parts to Cover when Cleaning an Engine?
A: Make sure you cover sensitive parts of the engine before you start, such as:
You don’t need anything fancy either – some plastic bags will do, just tape them into place if needs be.
Q: How to Remove Engine Sludge?
A: Engine sludge is a little different from the build up of oil and grease found on the engine surface. It builds up if you haven’t changed the oil in a while. The easiest way to tackle this is to add a chemical sludge remover to the oil and idle the engine for 10 minutes.
Then perform a full flush to remove the old oil (and sludge) and replace with fresh synthetic oil.