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Nulon Engine Oil Stop Leak 300ml - ESL
30%OFF

Nulon Engine Oil Stop Leak 300ml - ESL

$27.30
$39
Fitment Notes:
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Castrol Diesel Engine Flush 300ml - 3441133
55%OFF

Castrol Diesel Engine Flush 300ml - 3441133

$12
$23
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Nulon Engine Oil Flush 300ml - EOF
30%OFF

Nulon Engine Oil Flush 300ml - EOF

$24.50
$35
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Castrol Petrol Engine Flush 300ml - 3441131
55%OFF

Castrol Petrol Engine Flush 300ml - 3441131

$12
$23
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Repco Engine Oil Flush 300ml - REOF

Repco Engine Oil Flush 300ml - REOF

$16
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LIQUI MOLY Engine Flush Plus 300ml - 2784

LIQUI MOLY Engine Flush Plus 300ml - 2784

$27
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Explore 4WD & Adventure

Penrite Engine Flush 375ml - ADEF375

Penrite Engine Flush 375ml - ADEF375

$27
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Lucas Heavy Duty Oil Stabilizer 946ml - 10001

Lucas Heavy Duty Oil Stabilizer 946ml - 10001

$40
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Proma MBL8 Oil Concentrate 250ml - 50083

Proma MBL8 Oil Concentrate 250ml - 50083

$80
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Lucas Oil Engine Oil Stop Leak 946ml - 10278

Lucas Oil Engine Oil Stop Leak 946ml - 10278

$30
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Repco Lifter Free & Tune Up 300mL - RLFTU

Repco Lifter Free & Tune Up 300mL - RLFTU

$33
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Penrite Lifter and Tappet Fix 375ml - ADLTF375

Penrite Lifter and Tappet Fix 375ml - ADLTF375

$31
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Penrite Engine Oil Stop Leak 375ml - ADESL375

Penrite Engine Oil Stop Leak 375ml - ADESL375

$24
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LIQUI MOLY Engine Oil Resealer 300ml - 2782

LIQUI MOLY Engine Oil Resealer 300ml - 2782

$29
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Penrite Engine Stop Smoke 375mL - ADESS375

Penrite Engine Stop Smoke 375mL - ADESS375

$19
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Rislone Engine Oil Burning & Leak Repair 500ml - 44223

Rislone Engine Oil Burning & Leak Repair 500ml - 44223

$81
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Nulon Engine Stop Smoke 500ml - SS
Clearance

Nulon Engine Stop Smoke 500ml - SS

$10
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Rislone Engine Treatment Concentrate 500ml - 44102

Rislone Engine Treatment Concentrate 500ml - 44102

$23
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Morey's Oil Stabiliser 1L - MOS

Morey's Oil Stabiliser 1L - MOS

$35
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Rislone Rear Main Seal Repair 500ml - 44240

Rislone Rear Main Seal Repair 500ml - 44240

$38
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Nulon Upper Engine Cleaner 150gm - UEC150

Nulon Upper Engine Cleaner 150gm - UEC150

$29
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Rislone High Mileage Compression Repair 500ml - 4447

Rislone High Mileage Compression Repair 500ml - 4447

$38
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Nulon Lifter-Free/Tune-Up 300ml - LFTU
Clearance

Nulon Lifter-Free/Tune-Up 300ml - LFTU

$23
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Rislone Engine Oil Stop Leak Additive 325ml - 44209

Rislone Engine Oil Stop Leak Additive 325ml - 44209

$20
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Penrite Engine Boost+ 500ml - PSPEB0005
Clearance

Penrite Engine Boost+ 500ml - PSPEB0005

$10
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Repco Stop Smoke 300ml - RSS
Clearance

Repco Stop Smoke 300ml - RSS

$2
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Repco Oil Stabiliser 1L - ROS1L

Repco Oil Stabiliser 1L - ROS1L

$36
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Penrite Motor Cycle Foam Filter Kit  - MCFFCKIT

Penrite Motor Cycle Foam Filter Kit - MCFFCKIT

$167
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Repco Engine Oil Stop Leak 300ml - RESL

Repco Engine Oil Stop Leak 300ml - RESL

$32
Fitment Notes:
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Morey's Oil Stabiliser 5L - MOS5L
Clearance

Morey's Oil Stabiliser 5L - MOS5L

$108
Fitment Notes:
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Wynns Engine Flush 325ml

Wynns Engine Flush 325ml

$41
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Showing 1 - 33 of 33 products

Explore Repco’s Range of Engine Oil Additives

Repco offers a wide selection of engine oil additives designed to help maintain and improve engine performance. Whether it’s an engine flush to clean out sludge and deposits or a product like Lucas oil stabilizer to reduce oil consumption and improve sealing, there are options suited to a variety of engine needs. Popular choices include Liqui Moly engine flush and other specialist treatments that prepare the engine for fresh oil and help extend its life. These additives are practical solutions for both everyday drivers and enthusiasts who want to protect their investment and keep their engines running smoothly under real-world conditions.

Are oil additives good for your engine?

Oil additives are chemical compounds added to engine oil to enhance its properties and performance. They can improve lubrication, reduce wear, prevent corrosion, and help maintain engine cleanliness. Products such as Lucas oil stabilizer, Morey's oil stabiliser, and Rislone are popular examples designed to support engine health.

Oil additives can be beneficial in specific situations. For older engines showing signs of wear, oil stabilisers help reduce oil consumption and improve sealing. Some additives contain ingredients that address leaks, such as engine oil stop leak or rear main seal stop leak formulas, which can help reduce or prevent oil leaks without immediate mechanical repairs.

While oil additives provide benefits, they are not a substitute for regular maintenance or proper oil selection. Modern engine oils already contain many additives formulated by manufacturers. Using additional additives unnecessarily may not provide extra benefits and could even interfere with oil chemistry. It is important to choose the right product for your engine’s condition and follow the manufacturer’s instructions.

Can you add additives to synthetic oil?

Many oil additives are compatible with synthetic oils. Synthetic oils are engineered with advanced base stocks and additive packages, but additional engine oil additives can be used to target specific issues, such as reducing engine noise, improving seal conditioning, or preventing leaks.

When adding additives to synthetic oil, it is essential to select products designed for use with synthetic formulations. For example, Liqui Moly Ceratec is an engine oil additive that can complement synthetic oils by enhancing wear protection through ceramic technology.

Always check the additive’s label for compatibility and dosage instructions. Avoid mixing multiple additives unless recommended, as this can alter the oil’s performance characteristics. If unsure, consult with a professional or the product manufacturer.

How effective is engine oil flush?

Engine oil flush is a process that uses a chemical treatment to clean sludge, varnish, and deposits from the engine’s internal components before an oil change. Products like Penrite engine flush and Liqui Moly engine flush are formulated to dissolve contaminants and improve oil flow.

Using an engine oil flush can restore engine efficiency, reduce wear, and extend the life of engine components. It is particularly useful for engines that have experienced extended oil change intervals, heavy idling, or harsh operating conditions.

While effective, engine oil flush should be used with caution. In older engines with significant sludge buildup, the flush may dislodge deposits that can clog oil passages or filters. It is advisable to follow product instructions carefully and consider professional advice if the engine condition is uncertain.

How to use engine oil flush

To use engine oil flush, start by warming the engine to normal operating temperature. This helps the flush product circulate effectively. Add the recommended amount of engine oil flush, such as Penrite engine flush or Liqui Moly engine flush, to the engine oil through the filler cap.

Run the engine at idle for the time specified on the product label, usually between 10 to 15 minutes. Avoid driving the vehicle during this period to prevent dislodged deposits from circulating through the system.

After flushing, drain the engine oil completely and replace the oil filter. Refill with fresh, manufacturer-recommended engine oil. Using an engine oil additive or oil stabilizer after the flush can help maintain engine cleanliness and protection.

Should you use thicker oil or oil additives in older engines?

Older engines often develop increased clearances due to wear, which can lead to oil consumption and reduced oil pressure. Using thicker oil is one approach to compensate for these clearances, helping maintain oil pressure and reduce leaks.

Alternatively, oil additives like Lucas oil stabilizer or Morey's oil stabiliser can improve oil viscosity stability and help condition seals, reducing leaks such as rear main seal stop leak. Some additives also reduce friction and wear, supporting engine longevity.

Deciding between thicker oil and additives depends on the engine’s condition and manufacturer recommendations. Thicker oil may cause increased drag or reduced fuel efficiency if too heavy. Oil additives can be a cost-effective way to improve performance without changing oil grade. In some cases, combining both approaches under professional guidance provides optimal results.

Complete Your Maintenance with Repco’s Complementary Products

Alongside engine oil additives like engine oil flush and stabilisers, Repco stocks a comprehensive range of products to support vehicle maintenance. You can find quality oil filters to ensure clean oil circulation, fuel additives that help maintain fuel system efficiency, and cooling system products to prevent overheating. Together, these categories provide a complete toolkit for keeping engines in good condition and ready for the demands of Australian & New Zealand roads and conditions.