Best Oil Leak Additives Updated April 2026
Advertiser disclosure About our rankings

Join the millions that have trusted BuyersGuide.org to help them make smarter buying decisions. Let our independent expert reviews and data-driven shopping recommendations help you find the one that's right for you.

Best Oil Leak Additives
2026 Buyer's GuideUpdated April 2026
Advertiser disclosure About our rankings
Sort by:
Best Oil Leak Additive
Popular
1

10.0

Lucas Oil 10278 Engine Oil Stop Leak - 1 Quart
Performance
Quality
Value for money
Smooth operation
Noise level
1K+ bought in past month
Best Oil Leak Additive
Popular

10.0

1
Lucas Oil 10278 Engine Oil Stop Leak - 1 Quart
Performance
Quality
Value for money
Smooth operation
Noise level
1K+ bought in past month
Best Oil Leak Additive
Popular

10.0

1
Lucas Oil 10278 Engine Oil Stop Leak - 1 Quart
Available in:  2 sizes
Performance
Quality
Value for money
Smooth operation
Noise level
1K+ bought in past month
2

9.8

Bar's Leaks OS-1 Oil Seal Engine Oil Burning and Leak Repair, 16.9 oz.
Quality
Sealing
-18%

9.8

2
Bar's Leaks OS-1 Oil Seal Engine Oil Burning and Leak Repair, 16.9 oz.
Quality
Sealing
-18%

9.8

2
Bar's Leaks OS-1 Oil Seal Engine Oil Burning and Leak Repair, 16.9 oz.
Available in:  2 sizes
Quality
Sealing
-18%
3

9.6

ATP Automotive AT-205 Re-Seal Stops Leaks, 8 Ounce Bottle (2 Pack)
Functionality
Quality
Seal rejuvenation
Value for money
Lubrication

9.6

3
ATP Automotive AT-205 Re-Seal Stops Leaks, 8 Ounce Bottle (2 Pack)
Functionality
Quality
Seal rejuvenation
Value for money
Lubrication

9.6

3
ATP Automotive AT-205 Re-Seal Stops Leaks, 8 Ounce Bottle (2 Pack)
Functionality
Quality
Seal rejuvenation
Value for money
Lubrication
4

9.5

Permatex 30302 Engine Oil - Stop Leak, 12 fl oz, Effectively Stops and Prevents Oil Leaks and Burning Without Needing to Disman...

9.5

4
Permatex 30302 Engine Oil - Stop Leak, 12 fl oz, Effectively Stops and Prevents Oil Leaks and Burning Without Needing to Disman...

9.5

4
Permatex 30302 Engine Oil - Stop Leak, 12 fl oz, Effectively Stops and Prevents Oil Leaks and Burning Without Needing to Disman...
Available in:  4 styles
5

9.3

XADO ATOMEX Oil Additive Stop Leak Engine - Restore Seal and Gaskets, Treatment for Car Engine High Mileage or Rear Main Seal, ...
Effectiveness
Quality
-30%

9.3

5
XADO ATOMEX Oil Additive Stop Leak Engine - Restore Seal and Gaskets, Treatment for Car Engine High Mileage or Rear Main Seal, ...
Effectiveness
Quality
-30%

9.3

5
XADO ATOMEX Oil Additive Stop Leak Engine - Restore Seal and Gaskets, Treatment for Car Engine High Mileage or Rear Main Seal, ...
Effectiveness
Quality
-30%
6

9.2

Lucas Oil 10279 Engine Oil Stop Leak - 1 Gallon
Effectiveness
Quality
Value for money

9.2

6
Lucas Oil 10279 Engine Oil Stop Leak - 1 Gallon
Effectiveness
Quality
Value for money

9.2

6
Lucas Oil 10279 Engine Oil Stop Leak - 1 Gallon
Available in:  4 sizes ,  3 options
Effectiveness
Quality
Value for money
7

9.1

LIQUI MOLY Motor Oil Saver | 300 ml | Oil additive | SKU: 2020
Effectiveness
Quality
Oil consumption
Value for money
Noise level

9.1

7
LIQUI MOLY Motor Oil Saver | 300 ml | Oil additive | SKU: 2020
Effectiveness
Quality
Oil consumption
Value for money
Noise level

9.1

7
LIQUI MOLY Motor Oil Saver | 300 ml | Oil additive | SKU: 2020
Effectiveness
Quality
Oil consumption
Value for money
Noise level
Premium Pick
8

9.0

Bar's Leaks High Mileage Engine Repair-It, Pack of 4
Quality
Value for money
Noise level
Performance
Premium Pick

9.0

8
Bar's Leaks High Mileage Engine Repair-It, Pack of 4
Quality
Value for money
Noise level
Performance
Premium Pick

9.0

8
Bar's Leaks High Mileage Engine Repair-It, Pack of 4
Available in:  2 sizes
Quality
Value for money
Noise level
Performance
9

8.9

Bar's Leaks 1000 High Mileage Engine Repair, 16.9 oz | Restores Performance, Increases Compression & Horsepower, Stops Leaks, N...
Quality
Value for money
Noise level
Performance
-7%

8.9

9
Bar's Leaks 1000 High Mileage Engine Repair, 16.9 oz | Restores Performance, Increases Compression & Horsepower, Stops Leaks, N...
Quality
Value for money
Noise level
Performance
-7%

8.9

9
Bar's Leaks 1000 High Mileage Engine Repair, 16.9 oz | Restores Performance, Increases Compression & Horsepower, Stops Leaks, N...
Available in:  2 sizes
Quality
Value for money
Noise level
Performance
-7%
Best Value
10

8.7

STP High Mileage Oil Treatment + Stop Leak - 15 FL OZ
Functionality
Quality
Value for money
Engine noise
Oil consumption
Engine smoothness
Best Value

8.7

10
STP High Mileage Oil Treatment + Stop Leak - 15 FL OZ
Functionality
Quality
Value for money
Engine noise
Oil consumption
Engine smoothness
Best Value

8.7

10
STP High Mileage Oil Treatment + Stop Leak - 15 FL OZ
Available in:  2 sizes
Functionality
Quality
Value for money
Engine noise
Oil consumption
Engine smoothness

Our Top Choice

Best Oil Leak Additive
Popular
1

10.0

Lucas Oil 10278 Engine Oil Stop Leak - 1 Quart
Performance
Quality
Value for money
Smooth operation
Noise level
1K+ bought in past month
Best Oil Leak Additive
Popular

10.0

1
Lucas Oil 10278 Engine Oil Stop Leak - 1 Quart
Performance
Quality
Value for money
Smooth operation
Noise level
1K+ bought in past month
Best Oil Leak Additive
Popular

10.0

1
Lucas Oil 10278 Engine Oil Stop Leak - 1 Quart
Available in:  2 sizes
Performance
Quality
Value for money
Smooth operation
Noise level
1K+ bought in past month
Related Categories
Engine Oil AdditiveEngine Oil TreatmentHead Gasket SealerOctane BoosterAC Leak Stopper
How We Rank
Expert Analysis
Our team of experts highlights useful information so you can easily compare products to find the one that's right for you.

Award-Winning Tech
Our technology analyzes thousands of purchase trends to bring you the top product recommendations.

Why Trust Our Reviews?
1,000,000+ shoppers use Buyer's Guide every week to find the best products and services online.

Learn more about our rankings.

Reliable, Safe & Secure
Helping millions of users make smarter purchases online.
Related Categories
Engine Oil AdditiveEngine Oil TreatmentHead Gasket SealerOctane BoosterAC Leak Stopper
Related Categories
Engine Oil AdditiveEngine Oil TreatmentHead Gasket SealerOctane BoosterAC Leak Stopper