AT205 Reseal Vs. Blue Devil: Which One Is Better?

Our editors pick the products & services we write about. When you buy through our links, we may get a commission. Learn more.

AT205 Reseal and Blue Devil are two of the best products for stopping engine leaking. And you are confused about the choice to make between these products.

An engine starts leaking due to ageing and consistent use. It is quite annoying to pull your vehicle off the road for a minor leak. And, these stop leak oils can save you the expense of hundreds of dollars in a mechanic’s shop.

This article will make your decision easier with all of the specs and detailed comparisons you need to decide between two of the best oil stop leak products, AT205 Reseal and Blue Devil.

AT205 Reseal vs. Blue Devil: Comparison chart

The table below provides the most important information about Blue Devil and AT205 Reseal. It will help you to compare a summary of their properties.

AT-205 Reseal
Check Price
Blue Devill
Check Price
Customer Rating
CompatibilityHydraulic oil, gear oil, power steering fluids, Synthetic and conventional lubricants.Antifreeze and coolants.
Time to reach efficiency5 hours2 hours
ApplicationTo stop any leaks in the transmission, hydraulic network (excluding the brakes), or power steering system of a vehicle.To recondition any worn-out seals and repair blown head gaskets, freeze plugs, and heater cores.
TechnologyIt works based on the toughness and malleable properties of AT-205 - a compound used in rubber production.It works by bonding to cast, plastic, alloy, aluminum, or any material in the leakage area.
Safe for Gas & Diesel engines

AT205 Reseal vs. Blue Devil: Detailed Comparison

To choose the best between these two sealants, let’s go into further details about their specifications. We will compare them based on the following features.

How do they work?

AT205 Reseal

AT205 Reseal stop leaking oil is a product that can be used to fix oil leaks. It is easy to use and can be applied to various types of surfaces. It is also resistant to high temperatures and has a long shelf life. AT205 Reseal stop leaking oil is an effective way to stop oil leaks and prevent them from happening again.

AT Reseal is a watery compound that works by strengthening the chemical bonds in rubber seals and gaskets. It operates on the same principle used in the manufacture of rubber and flexible materials. Moreover, AT205 can be used in any engine, transimission, differential, braking system or power steering system.

Below is the usage chart of AT205 Reseal that recommends due to blending properties with oil:

System CapacityOunces of AT-205Approx. Bottels
12 quarts16oz2
10 quarts14oz1 2/3
8 quarts12oz1 1/3
6 quarts8oz1
4 quarts6oz2/3
2 quarts3oz1/3
1 quarts1.5oz1/6
An easy way to stop leaks for DIY – John Angel

Some feedbacks about AT-205

“I used AT-205 a couple of times on high mileage Hondas. Not 100% but it definitely seemed to help.”

JeffKeryk –

“AT205 works well for me. Put in engine and trans on my 69 ford and it’s not bone dry underneath but the spots on the garage floor are very minimal compared to before. I just ordered some to put in the 99 accord and 07 pilot.”

Ryanschillinger –

Blue Devil

Blue Devil is a popular brand of automotive sealant. It is used to stop leaks in radiators, hoses, gaskets and other car parts. It is available in both liquid and gel forms. Blue Devil is a permanent sealant, so it will not need to be replaced after each use.

Blue Devil works by binding itself to plastic, rubber, aluminium, or any metal within the leakage region. It is free of any lumps or particulate matter that can clog the engine. This product can work with both diesel and gasoline engines.

Also, it is made of a special blend of oils and additives that can quickly seal leaks without harming your engine or transmission.


Winner: AT205

AT205 works well with gear oil, power steering oil, synthetic oil, and conventional oil. It is chemically inert towards these liquids. Blue devil also mixes well with various types of engine fluids, antifreeze, and fresh coolants. However, it is not quite compatible with synthetic oil. Generally, the Blue devil doesn’t combine well with strong oxidants.

Both products don’t contain any petroleum distillate compounds. Petroleum distillates are known for causing rubber seals to break down. Remember not to place any of the liquids close to flame or heat.


Winner: AT205

AT 205 reseal uses plasticizers to seal leaky gaskets. Plasticizers reduce the stiffness of polymers while increasing their flexibility, ductility, and toughness. This chemical compound also finds its use in the production of films, PVCs, and any material that requires flexibility.

Blue Devil is a colourless and odourless liquid made from diethylene glycol. Diethylene glycol is a non-corrosive and non-clogging organic compound. It also has dehydration properties that can prevent fluid leakage.

Read more: Lucas Vs. Seafoam Vs. Chevron Techron


Winner: AT205

AT205 is strikingly easy to use. It works for rubber seals and gaskets within any engine. If you have a leak in your hydraulic system, all you do is pour the reseal product into your hydraulic oil. AT205 will move through the plastic and rubber seals within the system.

If it encounters any hole or space, it blocks them off. However, note that AT205 is capable of dissolving paint. Once you apply this sealant, remember to drive your vehicle for a while to allow proper circulation.

If you don’t do this, the product might attack any paint it comes across and cause it to congest your engine. Also, don’t use AT205 in your brake system.

Blue Devil is capable of reconditioning shrunken seals without damaging any engine component. This formula can be applied to gearboxes, axle seals, pinion seals, and rear differentials. Also, you don’t need to flush your cooling system or remove your thermostat before using it. One downside of Blue Devil is that it cannot repair largely failed gaskets.

Time required to reach efficiency

Winner: Blue Devil

The Blue Devil takes about two hours to work. Within 100 miles of driving, you should see any leaks stopping. On the other hand, ATP AT205 reseal needs 5 hours before it produces any visible results.

Reliability of results

Winner: AT205

Reviews from people who have used both products show that AT205 produces more long-lasting results. Its only major drawback is that it can make your engine produce blue smoke in some cases.

Blue Devil may require days or a few weeks before it can stop extreme leaks. Its effectiveness depends largely on your engine system. It is best to use it on V-6 and inline-four engines.


Winner: AT205

When it comes to choosing the right product to fix your car, you want to make sure you’re getting the best bang for your buck. Two of the most popular options on the market are AT205 Reseal and Blue Devil. But which one is better?

The AT205 is cheaper than Blue Devil. Also, it is a better choice if you’re looking for something that’s more affordable. If you’re looking for the best possible product, regardless of price, then Blue Devil is the way to go. It’s a little more expensive, but it’s worth it for the quality.

Therefore, the efficiency to cost ratio of AT2015 is higher compared to Blue Devil. However, the price difference between these two products is not much.


1. Do I need to perform a fresh oil change before I use AT-205?

No. You can use AT-205 at any point in between oil changes

2. Will AT-205 over-swell my seals?

Of course no. Because the most common cause of over swelling seals is petroleum distillates which are not found in this product.


Blue Devil and AT-205 reseal are two great products that can prevent those oil puddles under your vehicle. After a thorough comparison, AT-205 is the better product. This sealant is compatible with almost any type of engine. It also mixes well with other fluids within a vehicle’s system.

AT205 reseal provides more value compared to its price. Despite the fact that AT205 takes a longer time to circulate through the engine, it promises more permanent results compared to Blue Devil.

Read more: How Fast Can You Drive in 4×4 High & Low?

Helpful resources:


Leave a Comment

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.