Best Rtv Silicone for Valve Covers (2026): 5 Compared

Oil weeping down the side of a valve cover leaves a stain on the driveway and a smell under the hood, and a failed gasket is often the cause. A tube of RTV silicone forms a gasket in place, sealing the cover without a pre-cut part. This guide compares the best rtv silicone for valve covers, looking only at what each listing states about temperature range, pack size, skin time and warranty.

GarageToolHQ earns a commission when you buy through links on this page, at no extra cost to you. Read our affiliate disclosure.

Picks for the garage

#	Product	Shop Score	Buy
1	RTV Silicone Gasket Maker 9OZ (255g) Black	9.7/10	Buy on Amazon
2	A-Premium Black RTV Silicone Sealant Gasket Maker	9.7/10	Buy on Amazon
3	RTV Silicone Gasket Maker, Grey, 2-Pack	9.6/10	Buy on Amazon
4	Akfix HT300 High Temp Silicone Gasket Maker	9.6/10	Buy on Amazon
5	Black RTV Silicone Gasket Sealant High Temperature	9.5/10	Buy on Amazon

1

RTV Silicone Gasket Maker 9OZ (255g) Black

Prixzelkym·9.7/10 Shop Score

i

The Shop Score runs from 9.2 to 9.8 and weighs performance (35%), build (25%), value (25%), safety (10%, where it applies) and warranty (5%), using only what the manufacturer and the listing publish. How we pick ›

A 3-pack of 3 oz black RTV silicone tubes totaling 9 oz, rated from -65 to 572 in Fahrenheit, with a tube squeezer and a stated 1 YEAR warranty.

Check price on Amazon

Pros

• 3 tubes in the pack, for spares across jobs
• Lowest Fahrenheit low figure here at -65
• Tube squeezer included for even extrusion
• Stated 1 YEAR warranty

Cons

• No skin or set time stated beyond quick dry
• Black only in this listing
• Three small tubes to manage instead of one large tube
• Title total of 9 oz needs the bullet count to parse

2

A-Premium Black RTV Silicone Sealant Gasket Maker

A-Premium·9.7/10 Shop Score

i

The Shop Score runs from 9.2 to 9.8 and weighs performance (35%), build (25%), value (25%), safety (10%, where it applies) and warranty (5%), using only what the manufacturer and the listing publish. How we pick ›

A single 3 oz black RTV silicone sealant rated from -54 to 340 in Celsius, sensor safe, oil and water resistant, with a stated one-year unlimited-mileage guarantee.

Check price on Amazon

Pros

• Widest Celsius top figure here at 340
• Sensor-safe, non-corrosive formula stated
• Oil, water, transmission fluid, coolant and brake fluid resistance stated
• Stated one-year unlimited-mileage guarantee

Cons

• Single tube only, no spare in the box
• No skin or set time stated
• No color choice stated beyond black
• Guarantee limited to the cost of the item, per the spec table

3

RTV Silicone Gasket Maker, Grey, 2-Pack

Tylove·9.6/10 Shop Score

i

The Shop Score runs from 9.2 to 9.8 and weighs performance (35%), build (25%), value (25%), safety (10%, where it applies) and warranty (5%), using only what the manufacturer and the listing publish. How we pick ›

A grey 2-pack RTV silicone gasket maker rated from -50 to 590 in Fahrenheit, with non-slump paste that skins over in 15 minutes, and a 100% non-corrosive formula.

Check price on Amazon

Pros

• Skins over in 15 minutes for faster reassembly
• 100% non-corrosive, protecting oxygen sensors
• Non-slump paste stays in place on vertical surfaces
• Meets OEM specifications, per the listing

Cons

• No per-tube size stated in the listing
• No warranty term stated
• Grey only in this listing
• Top figure of 590 is in Fahrenheit, not Celsius

4

Akfix HT300 High Temp Silicone Gasket Maker

Akfix·9.6/10 Shop Score

i

The Shop Score runs from 9.2 to 9.8 and weighs performance (35%), build (25%), value (25%), safety (10%, where it applies) and warranty (5%), using only what the manufacturer and the listing publish. How we pick ›

A red 2-pack Akfix HT300 silicone gasket maker of 2 tubes of 10.1 fl oz, heat resistant to 482 permanent and 572 temporary in Fahrenheit, per the bullets.

Check price on Amazon

Pros

• Largest tube size here at 10.1 fl oz each
• 100% silicone mastic joint sealant stated
• Will not crack, shrink or become brittle, per the listing
• Waterproof performance in most conditions, per the listing

Cons

• No warranty term stated
• Dries slowly, per the listing
• Red only in this listing

5

Black RTV Silicone Gasket Sealant High Temperature

Realth·9.5/10 Shop Score

i

The Shop Score runs from 9.2 to 9.8 and weighs performance (35%), build (25%), value (25%), safety (10%, where it applies) and warranty (5%), using only what the manufacturer and the listing publish. How we pick ›

A single black RTV silicone tube of 3.53 oz rated from -60 to 280 in Celsius, working on metals, glass and wood, and setting completely after 24H.

Check price on Amazon

Pros

• Works on metals, glass and wood, per the listing
• More oil resistant than conventional silicone, per the listing
• Low odor and non-corrosive, per the listing
• Made under ISO 9001 Quality Systems, per the listing

Cons

• Lowest Celsius top figure here at 280
• Single tube only at 3.53 oz
• No warranty term stated
• Full set takes 24H, the slowest stated time here

Compared on paper

These numbers are the tool makers’ rated figures, as their listings print them on 30 October 2026. Temperature ranges follow each listing’s own units, since listings mix Fahrenheit and Celsius. “Not stated” means the listing does not give the figure.

How the points were given

Each sealant is scored on performance, build, value, safety and warranty, using only what the listing publishes. None of the five listings states a safety certification, so every sealant scores zero for safety. Two listings state a warranty term.

We map each tool’s weighted total onto a 9.2 minimum and 9.8 maximum in a straight line, so the point order and score order match. Only powered tools, or tools with stated safety features, get safety points. Everything else is rated out of 90.

Best rtv silicone for valve covers: buying guide

Temperature range first

Range is the deciding spec, and each listing states it in its own units. In Celsius, A-Premium states -54 to 340, the highest top figure here, against Realth at -60 to 280. In Fahrenheit, Prixzelkym states -65 to 572, against Tylove at -50 to 590. Akfix states 482 permanent and 572 temporary, so read both figures rather than the title figure alone. Match the range to the job in the listing’s own units, and never convert between them on guesswork.

Sensor safe and non-corrosive

Modern engines carry oxygen sensors and control modules that some sealants can harm. A-Premium states a sensor-safe, non-corrosive formula, neutral to aluminum, cast iron and steel, with no aggressive acids, amines or solvents. Tylove states a 100% non-corrosive formula protecting oxygen sensors and aluminum parts. The other listings do not state sensor safety, so treat sensor protection as a stated feature of those two only.

Pack size and skin time

Pack sizes run from a single tube to a 3-pack, and a spare tube matters when a second cover needs sealing. Prixzelkym sells 3 tubes of 3 oz with a tube squeezer, Tylove and Akfix sell 2-packs, and A-Premium and Realth sell single tubes. On timing, Tylove skins over in 15 minutes for faster reassembly, Realth sets completely after 24H, and Akfix notes that it dries slowly.

Color and uses

Colors here are black, grey and red, and no listing ties color to performance. Uses named across the listings cover valve covers, oil pans, timing covers, water pumps, transmission housings and differential covers. A-Premium also names thermostat housings, exhaust manifolds and turbocharger flanges, while Realth names the widest spread, from oven doors to pipe joints. For a valve cover job, any of the five names the cover in its uses.

Warranty

Two listings state a warranty term. Prixzelkym states a 1 YEAR warranty, and A-Premium states a one-year unlimited-mileage guarantee, limited to the cost of the item per its spec table. The Tylove, Akfix and Realth listings state no warranty term, so those three score zero for warranty here.

Garage Fit Check

• Check the temperature range in the listing’s own units before ordering.
• Match the sealant to the job: valve cover, oil pan, timing cover and water pump uses are all named in these listings.
• Confirm pack count: single tubes, 2-packs and a 3-pack appear here.
• Note the skin and set times: Tylove skins in 15 minutes, Realth sets completely after 24H.

FAQ: garage tools

What temperature range do I need for a valve cover?

Match the listing range to the job in its own units. A-Premium states -54 to 340 in Celsius, Prixzelkym states -65 to 572 in Fahrenheit, and Tylove states -50 to 590 in Fahrenheit.

Is RTV silicone sensor safe?

Two listings state it. A-Premium states a sensor-safe formula, and Tylove states a 100% non-corrosive formula protecting oxygen sensors. Sensor safety is Not stated for the other listings.

How long does RTV take to skin or set?

Tylove skins over in 15 minutes, and Realth sets completely after 24H. Akfix notes that it dries slowly, and the other listings state no skin or set time.

Does color matter?

The listings offer black, grey and red, and no listing ties color to performance. Choose by temperature range, pack size and warranty instead.

What warranty do these sealants carry?

Prixzelkym states a 1 YEAR warranty, and A-Premium states a one-year unlimited-mileage guarantee. The other listings state no warranty term.

More garage guides

See the engine and shop equipment hub, the best tire pressure gauge, the best torque wrench and the best car wax guides for the rest of the garage.