Loctite vs Permatex – Thread Sealant & Threadlocker Comparison

Permatex and Loctite are two of the biggest hitters in the adhesive market. Loctite is significantly more popular than Permatex – no surprise, as they have a ton more products – but in recent years, I’ve seen people recommending to use Permatex two. But, which is the better option out of the two?

The reality is that both of these products are extremely similar and you’re unlikely to notice a difference between the two. They both make sealants and threadlockers, so it’s important that you buy the right product for your needs.

It can be difficult to know which of these products would be best for each use, so lets go through some of their products and see which is best for each individual need.

Threadlocker vs Thread Sealants

It’s first essential to distinguish the difference between threadlockers and thread sealants, as although they perform completely different roles, many people get them confused – especially if you’re new to using these types of products. Fortunately, it’s pretty easy to distinguish between the two.

Threadlockers are used as an adhesive to help screws and bolts stay in place and help prevent them being exposed to leaks and corrosion. The colors of each threadlocker generally explain their strength, and how easy they are to remove from the thread.

Whereas, thread sealants are used generally for sealing up two connectors together, generally used for pipes and other metals.  A good thread sealant can help to fill the gap when you’re putting two pipes together and ensure now water escapes between the two.

It’s obviously worth working out which one of these you’re going to need before you purchase a product. Let’s have a look at the Loctite products first, then go onto the Permatex products afterwards.

Loctite Threadlockers

When I’m comparing products from different brands, using product codes can be particularly confusing It’s okay when you’re comparing the same brand products to each other – like Loctite 242 and 243 (which I wrote about in detail here)- but it makes it more difficult if you’re comparing it to other brands, as they don’t always line up.

So, I find it easier to use a color code system. I’ll do this for this comparison, and I’ll give you an example of a good product number to go for from each color!

Loctite Red – Permanent Sealing, High Strength

If you want to disassemble a thread put together with the red threadlocker, then you’ll need to use heat to get things done. Otherwise, it’ll be stuck there for eternity! Personally, I prefer Permatex's High Strength alternative, but each to their own.

Loctite Blue – Medium Strength

If you want a threadlocker that you can use for a variety of different things, then it’s a good idea to go for a general purpose medium strength one. Loctite 242 should be your first choice for this – the blue threadlocker works well for the majority of stuff e.g. most of the bolt threads on any of your appliances.

Loctite Heavy Duty Threadlocker, 0.2 oz, Blue 242, Single
  • Advanced formula prevents loosening of metal fasteners caused by vibrations
  • Protective design protects threads from rusting and corroding
  • Medium-strength allows nuts and bolts to be removed with hand tools
  • Locks and seals threaded fasteners that require disassembly

Loctite Purple – Low Strength

You don’t always need something that’s going to be high strength and locked in forever. Sometimes, a low strength sealant is better for your needs. Loctite 222 is their low strength threadlocker, and it’s ideal for use with aluminium and screws that will still need adjusting from time to time.

Loctite 222 Threadlocker for Automotive: High-Temp, Low-Strength, Anaerobic | Purple, 6mL Tube (PN: 38653-555339)
  • DESIGN. Ideal for fasteners under 1/4-Inches (6 mm) that require occasional adjustment.
  • RESULTS. Secure, one-piece assembly that will not loosen under stress.
  • SECURE. Locks and seals while preventing parts from loosening due to vibration.
  • EASY TO USE. Removable with hand tools for disassembly. Noncorrosive.
  • APPLICATION. Carburetors, relay locks, headlamps, throttle body assembly, choke assembly and fuel injection set screws and much more.

Loctite Green – Wicking Grade

Sometimes you need a threadlocker specifically designed to wick easily – this means that it’s a very low viscosity, and it can spread easily into the thread without you having to disassemble it. Loctite 290 is their most popular wicking threadlocker, and it’s one of their better products.

Loctite Thread Sealants

Loctite make an abundance of products, and although they’re well known for making threadlockers, they also make thread sealants too. Here are some of their best options if you need a thread sealant.

High Temperatures – Loctite 577

If you need a sealant that’s going to be exposed to high temperatures, then Loctite 577 is your best bet. It’s a medium strength sealant, but it works for temperatures as high as 200 degrees. The good thing about this one is that it works well with all metals, not just aluminium.

Quick working – Loctite 5776

Loctite 5776 is a good choice for outdoors machinery, as it’s a general purpose lubricant that works well for the majority of purposes. It works for both gas and water, for temperatures up to around 60 degrees.

Health and Safety – Loctite 5400

If you want something that works quickly for metal threads, then you can look at using Loctite 5400 which can be found here. It’s a good option if you need something that will work for pipes and other cylindrical appliances.

Permatex Threadlockers

You might not have anything against Loctite, but sometimes people prefer to opt for using Permatex (or maybe that’s the only one available!). There’s little difference between the brands, but it’s important to get the right type of Permatex for your needs. Getting the right one for you is easy, just make sure you pick the correct color for your needs! The colors are the same as with Loctite, so it’s much easier to follow the colors as opposed to their individual codes.

Permatex Red

Permatex Red is their high strength application, and you can use it for things like cap screws – just make sure you get the right dimensions.

Permatex 27100 High Strength Threadlocker Red, 6 ml
  • Adds 3,000 PSI holding power on slip and press fit assemblies
  • Well-suited for permanently locking studs and press fits
  • Replaces set screws and snap rings and also locks against vibration loosening
  • May require heat or special tools for removal
  • Suggested Applications: Cylinder block and rocker arm studs, ring gear bolts, frame bolts, shock absorber bolts

Permatex Blue

The general purpose threadlocker that Permatex produces is pretty great – I’ve used it myself plenty of times.

Permatex 24200 Medium Strength Threadlocker Blue, 6 ml
  • Locks and seals while preventing parts loosening due to vibration
  • Protects threads from corrosion
  • Ideal for all nut and bolt applications 1/4" to 3/4" (6mm to 20mm)
  • Removable with hand tools for easy disassembly
  • Suggested Applications: valve cover bolts, water pump bolts, oil pan bolts, drive shaft bolts, rocker arm adjustment nuts, carburetor studs

Permatex Purple

If you need something for small applications – think the headlamps on your car – then it could be worth considering Permatex Purple. It works well for all small applications and you can use it for a ton of stuff, especially on your vehicle.

Permatex 24024 Low Strength Threadlocker Purple, 6 ml Tube
  • Removable with hand tools for easy dissasembly
  • Noncorrosive
  • Designed for fasteners under 0.25 inch
  • Suggested Applications: Carburetors, relay locks, headlamps, throttle body assembly, body panel mounting fasteners, fine threads
  • OEM Specified

Permatex Thread Sealants

Of course, Permatex have their own range of thread sealants too. There really isn’t a lot of variety in these products – they have their regular thread sealant, but they also have one that’s specifically designed for being used in high temperatures.


The differences between these two brands is generally agreed to be considered as minimal. This is mainly because Permatex was actually owned by Loctite for a long time, so we can be sure that the vast majority of their products are very similar. Just be sure to get the right product for your needs, and you won’t need to worry about which brand is better – the differences are minimal.

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