All my life, I saw my car mechanic using Permatex Ultra Grey in the gaskets of the car. But the last time I went to the garage, I saw them trying out Permatex Motoseal, too, which surprised me a bit.
I came home, and I researched thoroughly about these two gasket makers to understand why my mechanic was trying the Motoseal, as well. After several days of research, I found the answer.
And if you are interested to know what I have found, keep on reading below.
Here, I have not only compared Permatex Motoseal vs. Ultra Grey in great detail but also explained why I chose one over the other for your better understanding.
So, dig in and learn what I have learned.
Read More: Permatex Ultra Grey vs. Ultra Black
Permatex Motoseal vs. Ultra Grey
Both the Permatex Motoseal and Permatex Ultra Grey are gasket makers from the very popular brand Permatex.
However, there are some significant differences between them that make them apart from one another.
I have listed these differences in the table below so that you can have a quick idea about them.
Comparison Table
| Features | Permatex Motoseal | Permatex Ultra Grey |
| Used For | Disassembled engines and two and four-cycle engines | High-torque and high-vibration applications in import engines |
| Application | Transmission case halves, valve covers, center and end covers (transmissions), crankcase halves, cam covers, timing chain cases, primary drives, side covers, and clutch housings | Valve covers, water pump, intake manifold end seals, thermostat housings |
| Cure Time | 20 minutes | 8 hours |
| Heat Resistant | Up to 350°F | Up to 500°F |
| Flexibility | Flexible | Not Flexible |
Read More: Permatex the Right Stuff Grey vs. Black
What Are The Differences Between Permatex Motoseal and Ultra Grey?
Not only the summary, but I have also discussed the differences in great detail so that you don’t find it difficult to differentiate between them.
Used For
Even though both the Permatex Motoseal and Ultra Grey are used on the gaskets and other engine parts in your car, when it comes to their usage, there is a significant difference.
For starters, the Permatex Motoseal gasket maker is usually used on the valve covers, center and end covers (transmissions), transmission case halves, crankcase halves, cam covers, and other parts of disassembled engines and two and four-cycle engines for your convenience.
It forms a highly effective seal and holds the components tightly in place.
On the other hand, Permatex Ultra Grey can effectively seal the water pump, intake manifold end seals, valve covers, and thermostat housings in high-torque import engines.
Even when there are high vibrations, you can use this gasket maker without any issues.
Read More: Permatex Form A Gasket 1 Vs. 3
Cure Time
The curing times of both the Permatex Motoseal and Ultra Grey differ greatly.
Even though the Permatex Motoseal gasket maker is more flexible, it takes just 20 minutes to seal and dry completely.
However, when it comes to Permatex Ultra Grey, the story is a bit different. This gasket maker takes about 8 hours to dry completely. You have to wait for such an amount of time before you can use the engine again.
Heat Resistant
Heat resistance is another aspect that draws differences between the Permatex Motoseal and Ultra Grey gasket makers.
Even though both these sealants can endure high heat, Permatex Motoseal can withstand 350°F of temperature while Permatex Ultra Grey can resist 500°F of heat before melting away.
Because of its high heat-resistant capabilities, Permatex Ultra Grey is more durable than Permatex Motoseal.
Read More: Permatex Ultra Copper Vs. Red
What is Permatex Ultra GREY used for?
Permatex Ultra GREY is a high-performance gasket maker and sealant used in automotive and mechanical applications.
It’s designed to create reliable and long-lasting seals for engine components, transmissions, differentials, and other automotive systems.
This product is typically used to replace traditional gaskets and is ideal for sealing flanges, valve covers, oil pans, water pumps, and more.
Is Permatex Ultra GREY good for oil?
Yes, Permatex Ultra GREY is designed to be oil-resistant. It is formulated to withstand exposure to various automotive fluids, including motor oil, transmission fluid, and gear oil.
This makes it suitable for applications where resistance to oil and other fluids is crucial, such as sealing oil pans and other engine components.
Is Permatex Ultra Black water-resistant?
Yes, Permatex Ultra Black is known for its water-resistant properties.
It’s designed to create effective and long-lasting seals that can withstand exposure to water and other liquids.
This makes it a good choice for various automotive and mechanical applications where resistance to water, oil, and other fluids is required, such as sealing gaskets, oil pans, and water pumps.
Last Opinion
As I have compared Permatex Motoseal vs. Ultra Grey in great detail, I can now say which of these gasket makers is my favorite.
Even though both these sealants have their own set of benefits and disadvantages, I advise you to pick Permatex Motoseal. That is because this gasket maker is highly flexible, sets up quickly, and is durable, too.
You can use this on various engine parts without any issues.
